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Diaphyseal reconstructions
Diaphyseal Reconstructions Valerae O. Lewis, MD,† and Paulose J. Paul, MD* Many malignant bony lesions are encountered in the diaphyseal segment of long bones. These lesions include Ewing’s sarcoma, adamantinoma, chondrosarcoma, and metastatic disease. The histology of the tumor, the size of the tumor, and the stage of the disease determine how the lesion should be treated. Metastatic lesions within the diaphysis can be treated with curettage and intramedullary stabilization. Primary bone tumors located in the diaphysis of the long bone should be treated with wide resection and reconstruction. There are many reconstructive options. The option utilized depends on the long bone involved, the extent of the resection, the age and the prognosis of the patient. The following article gives an overview of resection and reconstruction techniques for tumors located in the diaphyseal segment of long bones. Oper Tech Orthop 14:243-250 © 2005 Elsevier Inc. All rights reserved. KEYWORDS diaphysis, intercalary metal spacer, intercalary allograft, vascularized fibula
Resection Malignant tumors located in the diaphysis of long bones, by definition, do not involve the articular surfaces of the bone. Thus, resection and reconstruction of these tumors spares the proximal and distal joints and thus affords these patients excellent long-term functional outcome. In almost all cases, major arteries and nerves are not located directly on the periosteal surface of the bone and thus are spared during the resection. The notable exceptions occur in the radius and the humerus, with the radial artery and the radial nerve, respectively. These neurovascular structures are closely associated with diaphysis of these bones and hence may require resection.
Radius Malignant lesions of bone within the radial shaft are rare. Metastases are amenable to curettage and reconstruction. However, primary tumors should not undergo curettage and, if the lesion has a small or no soft tissue mass, en bloc resection can be performed. An Allen’s test should be performed preoperatively to ensure patency of both the ulnar and radial arteries. If both arteries are patent, one artery can safely be resected with the tumor without the risk of hand ischemia. Because of its location, the radial artery is most at risk for resection when en bloc resection of the radius is performed. Although, in oncologic surgery, the approach is dictated
*Division of Orthopaedic Surgery, University of Alberta, Edmonton, Alberta, Canada. †Section of Orthopaedic Oncology, MD Anderson Cancer Center, Houston, TX. Address reprint requests to Valerae O. Lewis, MD, Section of Orthopaedic Oncology, MD Anderson Cancer Center, PO Box 301402, Unit 444, Houston, TX 77230. E-mail: [email protected]
1048-6666/05/$-see front matter © 2005 Elsevier Inc. All rights reserved. doi:10.1053/j.oto.2004.11.021
by the location of the tumor and the soft tissue mass, the most common surgical approach to the radius is the volar approach of Henry— distally between flexor carpi radialis and the brachioradialis muscles and proximally between the pronator teres and the branchioradialis. If the radial neurovascular bundle can be preserved, it should be dissected away from the tumor. This is done by dividing the recurrent radial artery at the level of the biceps insertion into the radius. Exposure and dissection through the deeper layer of muscles—the supinator, the pronator teres, the flexor digitorum superficialis, and the pronator quadratus—is dependent on the extent of the lesion in the radius and involvement of these surrounding soft tissues. Proximally, the posterior interosseous nerve should be identified and protected as it passes through the supinator muscle. Supination of the forearm will bring the origin of the supinator into view and displace the posterior interosseous nerve laterally and posteriorly away from the surgical box. The supinator can be incised along its broad insertion. Pronate the arm to release the pronator teres from the radius. The dissection can be continued subperiosteally and the origin of the flexor digitorum superficialis detached. The dissection continues until the interosseous membrane is exposed. Distally, in order to reach bone, supinate the forearm and incise the periosteum of the lateral aspect of the radius, lateral to the pronator quadratus and flexor pollicus longus. The dissection can continue subperiosteally. The anterior interosseous artery and nerve are usually situated between the flexor pollicus longus and flexor digitorum profundus muscles. Depending on their involvement, these structures are resected with the tumor or retracted ulnarly, allowing safe exposure of the anterior shaft of the radius. In order for the rotational alignment of the radius to be reconstructed, the alignment of the radius should be marked before performing the osteotomy. Kirschner wires should be 243
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244 placed into the radius proximal and distal to the segment that is to be osteotomized. The osteotomies can be performed with an oscillating or Gigli saw. The radial segment can be elevated and the dorsal musculature detached with a cuff of soft tissue. Once the specimen is lifted free, and curettings from the intramedullary canal of the remaining radial segments should be sent to pathology for frozen section analysis to ensure the remaining bone is free of tumor.
Ulna Resection of lesions within the diaphysis of the ulna can be approached through an incision that overlies the dorsal subcutaneous border of the ulna. Resection of adjacent soft tissue is dependent on which muscular structures are involved, but generally the interval between the flexor carpi ulnaris and extensor carpi ulnaris muscles can be developed safely. As described for the radius, to mark rotation, Kirschner wires should be placed in line, proximal and distal to the segment to be resected. The osteotomies can then be made with an oscillating or Gigli saw, the free ulna segment can be rotated, and the anterior muscle structures—the flexor digitorum profundus, the extensor pollicis brevis, the adductor pollicis longus, and the interosseous membrane— can be released with a cuff of soft tissue remaining on the bone. The muscle belly of the flexor digitorum profundus, which lies immediately anterior to the ulna, should provide protection for the median and ulnar nerves.
Humerus The authors prefer the anterior approach to the diaphyseal humerus. It can be extended proximally into the deltopectoral approach of the shoulder and distally through the antecubital fossa to expose the elbow joint. The patient should be positioned in the beach chair position and the arm, from fingertips to axilla including the medial clavicle, should be prepped and draped. The incision can be made from the tip of the coracoid process distally in line with the deltopectoral groove and continue along the lateral aspect of the shaft of the humerus. Proximally, the plane lies between the deltoid and the pectoralis major. The insertions of the deltoid into the deltoid tuberosity and the pectoralis major into the lateral bicipital groove should be identified. Distally, the biceps should be retracted medially, being careful to identify and protect the musculocutaneous nerve. The plane between the medial and lateral fibers of the brachialis can be explored. Bone exposure need only be done proximal and distal to the extent of the lesion. After the osteotomy is performed, the segment can be rotated and the remaining soft tissues can be freed from the specimen. The location of the radial nerve in relation to the humerus and the tumor should be considered. The brachial artery, median and ulna nerves are generally well protected in a soft tissue envelope; however, the radial nerve runs posteriorly along the radial groove of the humerus. If the nerve is encompassed in the tumor, it should be resected with the specimen. If the lesion has displaced the nerve, then it may be possible to dissect the nerve off the tumor. If there is any question as to extent of tumor involvement of the nerve it should be resected, as function of the radial nerve can be reproduced with tendon transfers.
Femur The patient should be placed in the supine position with a bump under the buttock. The hindquarter, from the umbilicus to the toes, should be prepped and draped. A well-padded pneumatic tourniquet should be placed on the proximalmost portion of the limb and inflated. The standard lateral approach to the femur can be used with the incision extending from the lateral knee joint line proximally to the greater trochanter. Dissection is then taken through the skin, subcutaneous tissues, and fascial layer, in line with the incision. The vastus lateralis can be lifted from the underlying septum through the entire length of the femur, and proximally it can be elevated from the vastus ridge anteriorly. The vastus intermedius, either in its entirety or a significant portion of the muscle, can be left covering the tumor, providing a soft tissue margin. The gluteus maximus muscle insertion should be released. The intermuscular septum can then be cut and hamstrings dissected from the posterior aspect of the femur. The sciatic nerve lies protected within the posterior musculature. The artery and vein should be identified distally and posteriorly and protected throughout the case. The perforating vessels should be ligated and tied as they enter the femur. The vastus intermedius should be bisected proximally and distally at the level desired for the femoral osteotomy. Rotation should be marked proximal and distal to the osteotomy. The distal femoral osteotomy can then be performed. The marrow from the remaining femur should be sent to pathology for frozen section analysis to ensure the remaining bone is free of tumor. A Lane bone holding retractor can then placed on the cut specimen to elevate the femur so that the medial dissection can be completed. The multiple feeding vessels to the tumor should be ligated and tied along the vascular bundle. The branching vessels of the deep profundus should be ligated. Now that the femur is circumferentially exposed, the proximal osteotomy can be performed at the desired level. The proximal marrow margin should be sent to pathology for frozen section analysis.
Tibia Extensile exposure of the tibia follows the anteromedial subcutaneous border of the bone. Since the bone is subcutaneous over most of its length, if there is anterior soft tissue involvement or an anterior biopsy tract that must be excised with the lesion, soft tissue reconstruction may be required for coverage following bony reconstruction. The patient should be placed in the supine position. The lower extremity, from toes to groin should be prepped and draped. A well-padded tourniquet should be placed on the proximal portion of the limb and inflated. A longitudinal incision can be made over the anterior aspect of the tibia just medial to the crest of the tibia. As with all oncologic resections, in the area of the soft tissue mass and/or biopsy site, the skin should be ellipsed. Dissection is performed through the fascia in line with the incision. Laterally, the fascia overlying the tibialis anterior is incised. The tibialis anterior is freed from the tibia, taking care to leave a portion of the muscle covering the soft tissue mass and providing a soft tissue margin. The dissection should be continued posterolaterally to the interosseous membrane. The anterior tibial artery and the deep peroneal nerve should be identified and protected. The
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Figure 1 Dual incision approach for hemicortical resection and reconstruction distal femur.
multiple feeding vessels should be ligated and tied along the vascular bundle. The interosseous membrane is then bisected, exposing the posterior compartment. Medially, the fascia overlying the gastrocnemius soleus mechanism should be incised. The soleus can be released from the tibia and the dissection can be continued posteriorly through the flexor digitorum longus and the tibial posterior. A portion of the flexor digitorum longus and the tibialis posterior can be left with the tibia to serve as a posterior soft tissue margin. The posterior tibial artery and vein, the peroneal artery and vein, and the tibial nerve are protected deep to the posterior tibialis. Tibia alignment/rotation should be marked before the osteotomy. The osteotomy is performed at the desired level. The specimen is elevated from the resection bed, putting any remaining soft tissue attachments on stretch. The remaining soft tissue can be bisected. Proximal and distal marrow margins should be sent for immediate pathological analysis.
Hemicortical Allograft Resection and Reconstruction—Distal Femur There are circumstances that do not require resection of the entire diaphysis of the bone, but only require hemicortical resection. An operative technique for hemicortical resection and allograft reconstruction has been described for lesion on the posterior aspect of the femur.1 This technique preserves the anterior cortex, spares the joint surface, and approaches the tumor through two separate incisions. The patient is positioned supine. A well-padded pneumatic tourniquet is placed on the proximal-most portion of the limb. The leg is elevated for two to three minutes, and the tourniquet is inflated. The knee is flexed to 75° and the foot is held to the operating table. A longitudinal incision is made on the medial aspect of the thigh, extending from the mid portion of the thigh to approximately 6 cm distal to the knee.
The fascia is opened and the interval between the vastus medialis and the sartorius is identified. The vastus medialis is retracted anteriorly and the gracilis and sartorius are retracted posteriorly. The femoral vein and artery are identified in the popliteal space and are retracted posteriorly. Small vascular branches to the distal part of the femur and the tumor are ligated and divided. The sciatic nerve is often not visualized as it is posterior to the plane of dissection. Distally, the medial head of the gastrocnemius is identified and cut 1 cm distal to its origin. The posterior part of the knee joint capsule is visualized. The medial aspect of the distal part of the femur is exposed, usually with some adductor magnus insertion left on the bone posterior to the site of the medial longitudinal osteotomy. A similar dissection is performed on the lateral side of the distal part of the femur. A longitudinal incision is made, extending from the midportion of the thigh to the Gerdy tubercle. The tensor fascia is opened in line with the incision. The vastus lateralis muscle is split longitudinally, with its osseous attachment to the femur left undisturbed along the incision to expose the lateral aspect of the distal part of the femur. The long head of the biceps is identified and is dissected free from the underlying short head. The posterior portion of the vastus lateralis and the short head of the biceps femoris are left attached to the femur and remain with the operative specimen. The popliteal space is identified through the dissection between the long and short heads of the biceps femoris muscle. The lateral head of the gastrocnemius is identified and is cut 1 cm distal to its origin. The posterior part of the knee joint capsule is visualized. Arthrotomies are made medially and laterally within the knee. The posterior part of the capsule is cut transversely just distal to its attachment on the femur. On the basis of preoperative studies used to determine the anatomical extent of the tumor and with use of cautery, the lateral and medial osteot-
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omy sites are demarcated along the cortex of the femoral shaft (Fig. 1). The medial and lateral longitudinal osteotomies and the proximal transverse osteotomy are made with an oscillating saw. The distal transverse osteotomy is the most difficult osteotomy. The tumor usually extends into the intercondylar notch, and the distal osteotomy must be distal to the tumor. This requires removal of a portion of the origin of the posterior cruciate ligament and a portion of both femoral condyles. The osteotomies of the medial and lateral condyles are started with an oscillating saw, but the central portion of the osteotomy is made with an osteotome. The resected tumor is now removed from the limb. Frozen section analysis is performed on the remaining bone. If there is a close or questionable margin, additional bone should be taken if the margin is inadequate. A fresh-frozen distal femoral allograft is fashioned to match the femoral defect and can be secured by lag-screw or plate and screw fixation. The incisions are closed over large suction drains. The wounds are dressed and the limb is placed in a posterior splint with the knee held in 15° to 30° of flexion.
Preoperative Planning All cases requiring resection and reconstruction should be templated preoperatively. A preoperative template or plan helps to improve the flow of surgery and facilitate the execution of the procedure. Preoperative planning should include determination of the resection length, using plain radiographs and magnetic resonance imaging, templating and ordering of a matched allograft or the endoprosthesis, templating of fixation devices using hand drawings or transparent radiograph overlays, ensuring all equipment is available and functioning, and review of the operative technique.
Reconstruction Intramedullary Fixation The development of rigid-interlocking intramedullary rods offers the option of rigid stabilization with limited exposure. An intramedullary rod can reinforce the host bone in the face of diaphyseal metastatic disease or pathological fractures, or it can be used for fixation of the intercalary allograft. The advantages of intramedullary fixation include its technical ease and its ability to stabilize the entire bone through limited exposure. Intramedullary rods offer stabilization; however, they will fail in the absence of bone healing at the fracture or osteosynthesis sites. When there is significant bone loss associated with the metastatic lesion or if curettage of the lesion has left a significant defect, many surgeons advocate the use of polymethylmethacrylate (PMMA) to provide structural support, increase the strength of the overall construct, and allow early weight bearing.2 Intramedullary fixation of the femur for metastatic disease is best performed using an antegrade device. A variety of methods for gaining access to the intramedullary canal are known to exist. The authors’ preferred method includes percutaneous insertion of a 2-mm guide wire through the skin and soft tissue into the femur. Proper location of the guide wire in both the anteroposterior (AP) and lateral planes must
Figure 2 (A and B) AP views of the proximal femur demonstrating spiral blade fixation of a metastatic lesion in the diaphysis of the femur and PMMA filing of the distal defect.
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247 as fixation for an intercalary allograft, the osteosynthesis junctions are often supplemented with plates. This platefixation not only provides rotatory stability, but also can provide compression at the osteosynthesis junctions.
Intercalary Allograft
Figure 3 Fixation of an intercalary allograft of the diaphysis of the tibia with long locking plate spanning the proximal and distal junctions. Note multiple screw holes left empty in the plate overlying the allograft. (Color version of figure is available online.)
be confirmed by fluoroscopy. A small incision is then made around the guide wire and a cannulated 14-mm reamer is then used to create the desired entry portal into the femur. A ball tip guide wire is then inserted down the femur. In the case of metastatic disease, the guide wire is inserted to just proximal to the diaphyseal lesion. If a large lytic lesion is present or if the tumor is not radiosensitive, the lesion can be curetted and, if needed, cemented. A second skin incision through which curettage of the lesion can be performed is created along the lateral aspect of the thigh at the level of the lesion. The fibers of tensor fascia lata and vastus lateralis are sharply incised to the lateral cortex of the femur. An oval cortical window is created using a sharp burr or a circular saw and the lesion is then curetted. Once the lesion is thoroughly curetted, the guide wire is passed distally down the diaphysis. Sequential intramedullary reaming of the bone can then proceed. Reaming should be performed slowly so as to minimize the risk of fat or tumor embolism. The reaming is continued until cortical interference is encountered at the isthmus of the diaphysis. To avoid high impact forces during insertion of the rod, the femoral canal should be reamed to 1.0-1.5 mm greater than the diameter of the rod inserted. The rod should be locked proximally and distally. In the face of metastatic disease the femoral neck should be stabilized (Fig. 2). Intramedullary stabilization of the humerus is performed via a similar procedure. In the humerus, the device must be well buried within the head of the humerus to prevent impingement symptoms, which can be quite debilitating. When curettage and cementation is performed on mid-diaphyseal lesions, the surgeon must be cognizant of the location and proximity of the radial nerve. Following insertion of the intramedullary device for metastatic disease the patient should be referred for radiation treatment to achieve local tumor control. To prevent additional lesions within the diaphysis, the entire operative field should be included in the radiation field. As discussed later, intramedullary rods can also be used as fixation for intercalary allograft reconstruction.3-5 When used
Intercalary allografts provide a permanent biologic solution for areas of segmental bone loss and thus offer an excellent option for reconstruction of diaphyseal defects.6 The advantages of the intercalary allograft reconstruction include its availability and lack of donor site morbidity. The potential disadvantages are the need for osteosynthesis union and thus delayed weight bearing, infection, and the risk of fracture.7,8 Some surgeons have advocated filling of the allograft with antibiotic impregnated PMMA to provide additional structural support and decrease the incidence of fracture.9 Following resection of the bony lesion, the resected specimen is measured on the back table. To thaw the allograft, the authors soak the allograft in warm saline with 50,000 units of bacitracin and 500,000 units of polymyxcin. Once thawed, the allograft should be stripped of any soft tissue attachments and the marrow contents removed. Some clinicians feel this reduces the amount of immunogenic material.10 The allograft is then cut to size. It is often useful to cut the allograft slightly longer than the defect, thus leaving additional bone to allow
Figure 4 AP radiograph demonstrating fixation of a tibia intercalary allograft with a locked tibial rod.
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Figure 5 (A) AP radiograph of a diaphyseal osteosarcoma of the femur in an 84-year-old male with metastatic disease. (B) AP radiograph of a metal intercalary spacer reconstruction.
for any final adjustments or manipulations that need to be made before final fixation. Fitting the graft into the surgical bed and aligning the host allograft junctions can be done with single plane or step-cut osteotomies. Fixation at the proximal and distal osteotomy sites can be achieved with the use of plate osteosynthesis or intramedullary fixation. Plate fixation provides rigid fixation and affords compression at the host-allograft junctions. Six to eight cortices on either side of the intercalary allograft are recommended. Fixation can be performed with single or dual plates, depending of the size of the defect and the length of plates required (Fig. 3). However, if two plates are used they should overlap to avoid the creation of a stress riser between the two devices. Fixation into the allograft must be done with care to avoid causing a fracture in the allograft bone. All screw holes in the plate over the allograft should not be filled. The allograft is harder and more brittle than the patient’s own bone and, as a result, screw insertion into the allograft can be associated with fracture. As discussed in the previous section, another option for fixation of the intercalary allograft is intramedullary fixation. Intramedullary fixation devices have the advantage of spanning the host-allograft junctions proximally and distally, not creating holes in the allograft, and intramedullary structural support even when the graft has healed (Fig. 4). The disadvantage of intramedullary fixation is the lack of rigid compression at the host-allograft junction sites. The combination of plate fixation and intramedullary fixation is an attractive compromise that allows stabilization of
the entire bony construct with the intramedullary device and rigid fixation and compression at the host-allograft junctions with plate osteosynthesis. Screws can be placed at oblique angles to avoid the intramedullary device. The advent of locking plates alleviates the need for oblique screws; unicortical locking screws provide rigid fixation and compression across the host-allograft junction. Some clinicians recommended the augmentation of the host-allograft junction with a vascularized fibula to facilitate union. This is especially helpful when the patient is receiving chemotherapy which can result in delayed bone healing.
Intercalary Autograft Autogenous strut bone graft is another reconstructive option for diaphyseal defects. Nonvascularized strut autografts have been used successfully to reconstruct intercalary defects up to 8 cm in length; however, vascularized autografts are advocated for the reconstruction of longer defects. Vascularized fibular reconstruction for segmental bone defects has been used in both lower and upper extremity reconstructions. Although some clinicians advocate vascularized fibula reconstruction for tibia defects in children, due to the small diameter of the fibula and lack of structural integrity, vascularized fibulas may be better suited for upper extremity reconstructions. When used in the lower extremity, the incidence of fracture is significant unless the extremity is protected. In the past, some clinicians have recommended dual fibular grafts for lower extremity lesions and single fibular grafts for the
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Figure 6 (A) Intraoperative photo of humeral diaphyseal resection. (B) Intraoperative photo of humeral diaphyseal reconstruction with metal intercalary spacer. (C) AP radiograph of the humeral metal intercalary spacer. (Color version of figure is available online.)
upper extremity.11,12 However, it has been shown that single vascularized fibular autografts undergo significant hypertrophy within 12 months of the reconstruction and thus may make dual fibular grafting unnecessary. Fixation of the fibular autograft can be achieved by plate or bicortical screw fixation. For short segments, a single compression plate can bridge both proximal and distal host-autograft junctions and is sufficient. Two plates may be needed for longer intercalary segments. To avoid the creation of a stress riser, the two plates should overlap by at least four screw holes. When the fibula can securely fit with the medullary canal of the resection defect, the graft can be secured proximally and distally with bicortical screws. A microvascular surgical team is needed for the vascular anastamosis, and the team should be consulted before initiating the procedure. The fixation of the graft should be completed before the microvascular reconstruction.
Endoprosthetic Replacement Diaphyseal defects can also be reconstructed with an intercalary metal spacer.13-15 The intercalary metal spacer offers the advantage of immediate stable fixation and hence immediate weight bearing. However, intercalary metal spacers have several drawbacks: limited stem length selection, the need for overdistraction to engage the male and female segments in the femoral version of the component, and a high failure rate
due to loosening of the prosthesis.13,16 This reconstruction technique has a limited life span and thus is only warranted in elderly patients, those patients with metastatic disease, or when a biologic reconstructive option is not available. The diaphyseal lesion should be resected as described above. Rotation should be marked, as previously described, with anterior cortical marks before removing the specimen from the resection bed. The resected specimen should be measured on the back table and an intercalary endoprosthetic device of similar length is constructed. In the past, intercalary metal spacers were custom. However, Stryker Orthopaedics (Mahwah, NJ) presently offers modular intercalary spacers so that the desired spacer length can be constructed intraoperatively. The stems of the intercalary spacers must be cemented. The canals should be prepared in the standard fashion by sequential reaming and each stem is cemented separately. Rotational alignment of each segment and the diaphysis is maintained by lining up the prosthesis and the anterior cortical marks made before resection of the specimen. In the femur, each segment of the intercalary spacer links to the next via a standard morse taper and complete assembly requires overdistraction of the segments to engage the morse taper (Fig. 5). In the humerus, the segments are not linked by a morse taper but are joined side-to-side and locked with a locking bolt (Fig. 6).
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Postoperative Rehabilitation For diaphyseal resections and reconstructions, the aim is early motion at the adjacent joints. All reconstructions should be of sufficient strength to allow immediate motion of the joints proximal and distal to the reconstruction. For intercalary reconstruction with allograft or autograft, the patient is non-weight bearing until radiographs demonstrate union at the host-graft junction. Muscular strength can be maintained with isometric exercises. The patient can fully weight bear once healing is demonstrated on the radiographs, 6 to 12 months postoperative. As stated previously, early weight bearing is permitted for endoprosthetic (metal spacer) reconstructions and intramedullary stabilization with PMMA.
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Summary Diaphyseal reconstruction of long bones following tumor resection can involve a variety of different surgical techniques. The technique used should be individualized on a case-bycase basis. In all cases, the oncological outcome is of paramount importance and should not be compromised. When used appropriately, the techniques described above allow surgical resection and limb-preserving reconstruction that restores satisfactory function.
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References 1. Lewis VO, Gebhardt MC, Springfield DS: Parosteal osteosarcoma of the posterior aspect of the distal part of the femur. Oncological and functional results following a new resection technique. J Bone Joint Surg Am 82A:1083-1088, 2000 2. Harrington KD, Sim FH, Enis JE, et al: Methylmethacrylate as an adjunct in internal fixation of pathological fractures. Experience with
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three hundred and seventy-five cases. J Bone Joint Surg Am 58:1047-1055, 1976 Mankin HJ, Doppelt SH, Sullivan TR, et al: Osteoarticular and intercalary allograft transplantation in the management of malignant tumors of bone. Cancer 50:613-630, 1982 Mankin HJ, Gebhardt MC, Jennings LC, et al: Long-term results of allograft replacement in the management of bone tumors. Clin Orthop 324:86-97, 1996 Mankin HJ, Springfield DS, Gebhardt MC, et al: Current status of allografting for bone tumors. Orthopedics 15:1147-1154, 1992 Muscolo DL, Ayerza MA, Aponte-Tinao L, et al: Intercalary femur and tibia segmental allografts provide an acceptable alternative in reconstructing tumor resections. Clin Orthop 426:97-102, 2004 Berrey BH Jr, Lord CF, Gebhardt MC, et al: Fractures of allografts. Frequency, treatment, and end-results. J Bone Joint Surg Am 72:825833, 1990 Lord CF, Gebhardt MC, Tomford WW, et al: Infection in bone allografts. Incidence, nature, and treatment. J Bone Joint Surg Am 70:369376, 1988 Gerrand CH, Griffin AM, Davis AM, et al: Large segment allograft survival is improved with intramedullary cement. J Surg Oncol 84:198208, 2003 Simon MA, Springfield D (eds): Surgery for Bone and Soft-Tissue Tumors. New York, NY, Lippincott-Raven, 1998 Jupiter JB, Ring D: Operative treatment of post-traumatic proximal radioulnar synostosis. J Bone Joint Surg Am 80:248-257, 1998 Mohler DG, Yaszay B, Hong R, et al: Intercalary tibial allografts following tumor resection: The role of fibular centralization. Orthopedics 26:631-637, 2003 Abudu A, Carter SR, Grimer RJ: The outcome and functional results of diaphyseal endoprostheses after tumour excision. J Bone Joint Surg Br 78:652-657, 1996 Heck DA, Chao EY, Sim FH, et al: Titanium fibermetal segmental replacement prostheses. A radiographic analysis and review of current status. Clin Orthop 204:266-285, 1986 Kuo KN, Gitelis S, Sim FH, et al: Segmental replacement of long bones using titanium fiber metal composite following tumor resection. Clin Orthop 176:108-114, 1983 Damron TA, Sim FH, Shives TC, et al: Intercalary spacers in the treatment of segmentally destructive diaphyseal humeral lesions in disseminated malignancies. Clin Orthop 324:233-243, 1996
Resection Malignant tumors located in the diaphysis of long bones, by definition, do not involve the articular surfaces of the bone. Thus, resection and reconstruction of these tumors spares the proximal and distal joints and thus affords these patients excellent long-term functional outcome. In almost all cases, major arteries and nerves are not located directly on the periosteal surface of the bone and thus are spared during the resection. The notable exceptions occur in the radius and the humerus, with the radial artery and the radial nerve, respectively. These neurovascular structures are closely associated with diaphysis of these bones and hence may require resection.
Radius Malignant lesions of bone within the radial shaft are rare. Metastases are amenable to curettage and reconstruction. However, primary tumors should not undergo curettage and, if the lesion has a small or no soft tissue mass, en bloc resection can be performed. An Allen’s test should be performed preoperatively to ensure patency of both the ulnar and radial arteries. If both arteries are patent, one artery can safely be resected with the tumor without the risk of hand ischemia. Because of its location, the radial artery is most at risk for resection when en bloc resection of the radius is performed. Although, in oncologic surgery, the approach is dictated
*Division of Orthopaedic Surgery, University of Alberta, Edmonton, Alberta, Canada. †Section of Orthopaedic Oncology, MD Anderson Cancer Center, Houston, TX. Address reprint requests to Valerae O. Lewis, MD, Section of Orthopaedic Oncology, MD Anderson Cancer Center, PO Box 301402, Unit 444, Houston, TX 77230. E-mail: [email protected]
1048-6666/05/$-see front matter © 2005 Elsevier Inc. All rights reserved. doi:10.1053/j.oto.2004.11.021
by the location of the tumor and the soft tissue mass, the most common surgical approach to the radius is the volar approach of Henry— distally between flexor carpi radialis and the brachioradialis muscles and proximally between the pronator teres and the branchioradialis. If the radial neurovascular bundle can be preserved, it should be dissected away from the tumor. This is done by dividing the recurrent radial artery at the level of the biceps insertion into the radius. Exposure and dissection through the deeper layer of muscles—the supinator, the pronator teres, the flexor digitorum superficialis, and the pronator quadratus—is dependent on the extent of the lesion in the radius and involvement of these surrounding soft tissues. Proximally, the posterior interosseous nerve should be identified and protected as it passes through the supinator muscle. Supination of the forearm will bring the origin of the supinator into view and displace the posterior interosseous nerve laterally and posteriorly away from the surgical box. The supinator can be incised along its broad insertion. Pronate the arm to release the pronator teres from the radius. The dissection can be continued subperiosteally and the origin of the flexor digitorum superficialis detached. The dissection continues until the interosseous membrane is exposed. Distally, in order to reach bone, supinate the forearm and incise the periosteum of the lateral aspect of the radius, lateral to the pronator quadratus and flexor pollicus longus. The dissection can continue subperiosteally. The anterior interosseous artery and nerve are usually situated between the flexor pollicus longus and flexor digitorum profundus muscles. Depending on their involvement, these structures are resected with the tumor or retracted ulnarly, allowing safe exposure of the anterior shaft of the radius. In order for the rotational alignment of the radius to be reconstructed, the alignment of the radius should be marked before performing the osteotomy. Kirschner wires should be 243
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244 placed into the radius proximal and distal to the segment that is to be osteotomized. The osteotomies can be performed with an oscillating or Gigli saw. The radial segment can be elevated and the dorsal musculature detached with a cuff of soft tissue. Once the specimen is lifted free, and curettings from the intramedullary canal of the remaining radial segments should be sent to pathology for frozen section analysis to ensure the remaining bone is free of tumor.
Ulna Resection of lesions within the diaphysis of the ulna can be approached through an incision that overlies the dorsal subcutaneous border of the ulna. Resection of adjacent soft tissue is dependent on which muscular structures are involved, but generally the interval between the flexor carpi ulnaris and extensor carpi ulnaris muscles can be developed safely. As described for the radius, to mark rotation, Kirschner wires should be placed in line, proximal and distal to the segment to be resected. The osteotomies can then be made with an oscillating or Gigli saw, the free ulna segment can be rotated, and the anterior muscle structures—the flexor digitorum profundus, the extensor pollicis brevis, the adductor pollicis longus, and the interosseous membrane— can be released with a cuff of soft tissue remaining on the bone. The muscle belly of the flexor digitorum profundus, which lies immediately anterior to the ulna, should provide protection for the median and ulnar nerves.
Humerus The authors prefer the anterior approach to the diaphyseal humerus. It can be extended proximally into the deltopectoral approach of the shoulder and distally through the antecubital fossa to expose the elbow joint. The patient should be positioned in the beach chair position and the arm, from fingertips to axilla including the medial clavicle, should be prepped and draped. The incision can be made from the tip of the coracoid process distally in line with the deltopectoral groove and continue along the lateral aspect of the shaft of the humerus. Proximally, the plane lies between the deltoid and the pectoralis major. The insertions of the deltoid into the deltoid tuberosity and the pectoralis major into the lateral bicipital groove should be identified. Distally, the biceps should be retracted medially, being careful to identify and protect the musculocutaneous nerve. The plane between the medial and lateral fibers of the brachialis can be explored. Bone exposure need only be done proximal and distal to the extent of the lesion. After the osteotomy is performed, the segment can be rotated and the remaining soft tissues can be freed from the specimen. The location of the radial nerve in relation to the humerus and the tumor should be considered. The brachial artery, median and ulna nerves are generally well protected in a soft tissue envelope; however, the radial nerve runs posteriorly along the radial groove of the humerus. If the nerve is encompassed in the tumor, it should be resected with the specimen. If the lesion has displaced the nerve, then it may be possible to dissect the nerve off the tumor. If there is any question as to extent of tumor involvement of the nerve it should be resected, as function of the radial nerve can be reproduced with tendon transfers.
Femur The patient should be placed in the supine position with a bump under the buttock. The hindquarter, from the umbilicus to the toes, should be prepped and draped. A well-padded pneumatic tourniquet should be placed on the proximalmost portion of the limb and inflated. The standard lateral approach to the femur can be used with the incision extending from the lateral knee joint line proximally to the greater trochanter. Dissection is then taken through the skin, subcutaneous tissues, and fascial layer, in line with the incision. The vastus lateralis can be lifted from the underlying septum through the entire length of the femur, and proximally it can be elevated from the vastus ridge anteriorly. The vastus intermedius, either in its entirety or a significant portion of the muscle, can be left covering the tumor, providing a soft tissue margin. The gluteus maximus muscle insertion should be released. The intermuscular septum can then be cut and hamstrings dissected from the posterior aspect of the femur. The sciatic nerve lies protected within the posterior musculature. The artery and vein should be identified distally and posteriorly and protected throughout the case. The perforating vessels should be ligated and tied as they enter the femur. The vastus intermedius should be bisected proximally and distally at the level desired for the femoral osteotomy. Rotation should be marked proximal and distal to the osteotomy. The distal femoral osteotomy can then be performed. The marrow from the remaining femur should be sent to pathology for frozen section analysis to ensure the remaining bone is free of tumor. A Lane bone holding retractor can then placed on the cut specimen to elevate the femur so that the medial dissection can be completed. The multiple feeding vessels to the tumor should be ligated and tied along the vascular bundle. The branching vessels of the deep profundus should be ligated. Now that the femur is circumferentially exposed, the proximal osteotomy can be performed at the desired level. The proximal marrow margin should be sent to pathology for frozen section analysis.
Tibia Extensile exposure of the tibia follows the anteromedial subcutaneous border of the bone. Since the bone is subcutaneous over most of its length, if there is anterior soft tissue involvement or an anterior biopsy tract that must be excised with the lesion, soft tissue reconstruction may be required for coverage following bony reconstruction. The patient should be placed in the supine position. The lower extremity, from toes to groin should be prepped and draped. A well-padded tourniquet should be placed on the proximal portion of the limb and inflated. A longitudinal incision can be made over the anterior aspect of the tibia just medial to the crest of the tibia. As with all oncologic resections, in the area of the soft tissue mass and/or biopsy site, the skin should be ellipsed. Dissection is performed through the fascia in line with the incision. Laterally, the fascia overlying the tibialis anterior is incised. The tibialis anterior is freed from the tibia, taking care to leave a portion of the muscle covering the soft tissue mass and providing a soft tissue margin. The dissection should be continued posterolaterally to the interosseous membrane. The anterior tibial artery and the deep peroneal nerve should be identified and protected. The
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Figure 1 Dual incision approach for hemicortical resection and reconstruction distal femur.
multiple feeding vessels should be ligated and tied along the vascular bundle. The interosseous membrane is then bisected, exposing the posterior compartment. Medially, the fascia overlying the gastrocnemius soleus mechanism should be incised. The soleus can be released from the tibia and the dissection can be continued posteriorly through the flexor digitorum longus and the tibial posterior. A portion of the flexor digitorum longus and the tibialis posterior can be left with the tibia to serve as a posterior soft tissue margin. The posterior tibial artery and vein, the peroneal artery and vein, and the tibial nerve are protected deep to the posterior tibialis. Tibia alignment/rotation should be marked before the osteotomy. The osteotomy is performed at the desired level. The specimen is elevated from the resection bed, putting any remaining soft tissue attachments on stretch. The remaining soft tissue can be bisected. Proximal and distal marrow margins should be sent for immediate pathological analysis.
Hemicortical Allograft Resection and Reconstruction—Distal Femur There are circumstances that do not require resection of the entire diaphysis of the bone, but only require hemicortical resection. An operative technique for hemicortical resection and allograft reconstruction has been described for lesion on the posterior aspect of the femur.1 This technique preserves the anterior cortex, spares the joint surface, and approaches the tumor through two separate incisions. The patient is positioned supine. A well-padded pneumatic tourniquet is placed on the proximal-most portion of the limb. The leg is elevated for two to three minutes, and the tourniquet is inflated. The knee is flexed to 75° and the foot is held to the operating table. A longitudinal incision is made on the medial aspect of the thigh, extending from the mid portion of the thigh to approximately 6 cm distal to the knee.
The fascia is opened and the interval between the vastus medialis and the sartorius is identified. The vastus medialis is retracted anteriorly and the gracilis and sartorius are retracted posteriorly. The femoral vein and artery are identified in the popliteal space and are retracted posteriorly. Small vascular branches to the distal part of the femur and the tumor are ligated and divided. The sciatic nerve is often not visualized as it is posterior to the plane of dissection. Distally, the medial head of the gastrocnemius is identified and cut 1 cm distal to its origin. The posterior part of the knee joint capsule is visualized. The medial aspect of the distal part of the femur is exposed, usually with some adductor magnus insertion left on the bone posterior to the site of the medial longitudinal osteotomy. A similar dissection is performed on the lateral side of the distal part of the femur. A longitudinal incision is made, extending from the midportion of the thigh to the Gerdy tubercle. The tensor fascia is opened in line with the incision. The vastus lateralis muscle is split longitudinally, with its osseous attachment to the femur left undisturbed along the incision to expose the lateral aspect of the distal part of the femur. The long head of the biceps is identified and is dissected free from the underlying short head. The posterior portion of the vastus lateralis and the short head of the biceps femoris are left attached to the femur and remain with the operative specimen. The popliteal space is identified through the dissection between the long and short heads of the biceps femoris muscle. The lateral head of the gastrocnemius is identified and is cut 1 cm distal to its origin. The posterior part of the knee joint capsule is visualized. Arthrotomies are made medially and laterally within the knee. The posterior part of the capsule is cut transversely just distal to its attachment on the femur. On the basis of preoperative studies used to determine the anatomical extent of the tumor and with use of cautery, the lateral and medial osteot-
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omy sites are demarcated along the cortex of the femoral shaft (Fig. 1). The medial and lateral longitudinal osteotomies and the proximal transverse osteotomy are made with an oscillating saw. The distal transverse osteotomy is the most difficult osteotomy. The tumor usually extends into the intercondylar notch, and the distal osteotomy must be distal to the tumor. This requires removal of a portion of the origin of the posterior cruciate ligament and a portion of both femoral condyles. The osteotomies of the medial and lateral condyles are started with an oscillating saw, but the central portion of the osteotomy is made with an osteotome. The resected tumor is now removed from the limb. Frozen section analysis is performed on the remaining bone. If there is a close or questionable margin, additional bone should be taken if the margin is inadequate. A fresh-frozen distal femoral allograft is fashioned to match the femoral defect and can be secured by lag-screw or plate and screw fixation. The incisions are closed over large suction drains. The wounds are dressed and the limb is placed in a posterior splint with the knee held in 15° to 30° of flexion.
Preoperative Planning All cases requiring resection and reconstruction should be templated preoperatively. A preoperative template or plan helps to improve the flow of surgery and facilitate the execution of the procedure. Preoperative planning should include determination of the resection length, using plain radiographs and magnetic resonance imaging, templating and ordering of a matched allograft or the endoprosthesis, templating of fixation devices using hand drawings or transparent radiograph overlays, ensuring all equipment is available and functioning, and review of the operative technique.
Reconstruction Intramedullary Fixation The development of rigid-interlocking intramedullary rods offers the option of rigid stabilization with limited exposure. An intramedullary rod can reinforce the host bone in the face of diaphyseal metastatic disease or pathological fractures, or it can be used for fixation of the intercalary allograft. The advantages of intramedullary fixation include its technical ease and its ability to stabilize the entire bone through limited exposure. Intramedullary rods offer stabilization; however, they will fail in the absence of bone healing at the fracture or osteosynthesis sites. When there is significant bone loss associated with the metastatic lesion or if curettage of the lesion has left a significant defect, many surgeons advocate the use of polymethylmethacrylate (PMMA) to provide structural support, increase the strength of the overall construct, and allow early weight bearing.2 Intramedullary fixation of the femur for metastatic disease is best performed using an antegrade device. A variety of methods for gaining access to the intramedullary canal are known to exist. The authors’ preferred method includes percutaneous insertion of a 2-mm guide wire through the skin and soft tissue into the femur. Proper location of the guide wire in both the anteroposterior (AP) and lateral planes must
Figure 2 (A and B) AP views of the proximal femur demonstrating spiral blade fixation of a metastatic lesion in the diaphysis of the femur and PMMA filing of the distal defect.
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247 as fixation for an intercalary allograft, the osteosynthesis junctions are often supplemented with plates. This platefixation not only provides rotatory stability, but also can provide compression at the osteosynthesis junctions.
Intercalary Allograft
Figure 3 Fixation of an intercalary allograft of the diaphysis of the tibia with long locking plate spanning the proximal and distal junctions. Note multiple screw holes left empty in the plate overlying the allograft. (Color version of figure is available online.)
be confirmed by fluoroscopy. A small incision is then made around the guide wire and a cannulated 14-mm reamer is then used to create the desired entry portal into the femur. A ball tip guide wire is then inserted down the femur. In the case of metastatic disease, the guide wire is inserted to just proximal to the diaphyseal lesion. If a large lytic lesion is present or if the tumor is not radiosensitive, the lesion can be curetted and, if needed, cemented. A second skin incision through which curettage of the lesion can be performed is created along the lateral aspect of the thigh at the level of the lesion. The fibers of tensor fascia lata and vastus lateralis are sharply incised to the lateral cortex of the femur. An oval cortical window is created using a sharp burr or a circular saw and the lesion is then curetted. Once the lesion is thoroughly curetted, the guide wire is passed distally down the diaphysis. Sequential intramedullary reaming of the bone can then proceed. Reaming should be performed slowly so as to minimize the risk of fat or tumor embolism. The reaming is continued until cortical interference is encountered at the isthmus of the diaphysis. To avoid high impact forces during insertion of the rod, the femoral canal should be reamed to 1.0-1.5 mm greater than the diameter of the rod inserted. The rod should be locked proximally and distally. In the face of metastatic disease the femoral neck should be stabilized (Fig. 2). Intramedullary stabilization of the humerus is performed via a similar procedure. In the humerus, the device must be well buried within the head of the humerus to prevent impingement symptoms, which can be quite debilitating. When curettage and cementation is performed on mid-diaphyseal lesions, the surgeon must be cognizant of the location and proximity of the radial nerve. Following insertion of the intramedullary device for metastatic disease the patient should be referred for radiation treatment to achieve local tumor control. To prevent additional lesions within the diaphysis, the entire operative field should be included in the radiation field. As discussed later, intramedullary rods can also be used as fixation for intercalary allograft reconstruction.3-5 When used
Intercalary allografts provide a permanent biologic solution for areas of segmental bone loss and thus offer an excellent option for reconstruction of diaphyseal defects.6 The advantages of the intercalary allograft reconstruction include its availability and lack of donor site morbidity. The potential disadvantages are the need for osteosynthesis union and thus delayed weight bearing, infection, and the risk of fracture.7,8 Some surgeons have advocated filling of the allograft with antibiotic impregnated PMMA to provide additional structural support and decrease the incidence of fracture.9 Following resection of the bony lesion, the resected specimen is measured on the back table. To thaw the allograft, the authors soak the allograft in warm saline with 50,000 units of bacitracin and 500,000 units of polymyxcin. Once thawed, the allograft should be stripped of any soft tissue attachments and the marrow contents removed. Some clinicians feel this reduces the amount of immunogenic material.10 The allograft is then cut to size. It is often useful to cut the allograft slightly longer than the defect, thus leaving additional bone to allow
Figure 4 AP radiograph demonstrating fixation of a tibia intercalary allograft with a locked tibial rod.
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Figure 5 (A) AP radiograph of a diaphyseal osteosarcoma of the femur in an 84-year-old male with metastatic disease. (B) AP radiograph of a metal intercalary spacer reconstruction.
for any final adjustments or manipulations that need to be made before final fixation. Fitting the graft into the surgical bed and aligning the host allograft junctions can be done with single plane or step-cut osteotomies. Fixation at the proximal and distal osteotomy sites can be achieved with the use of plate osteosynthesis or intramedullary fixation. Plate fixation provides rigid fixation and affords compression at the host-allograft junctions. Six to eight cortices on either side of the intercalary allograft are recommended. Fixation can be performed with single or dual plates, depending of the size of the defect and the length of plates required (Fig. 3). However, if two plates are used they should overlap to avoid the creation of a stress riser between the two devices. Fixation into the allograft must be done with care to avoid causing a fracture in the allograft bone. All screw holes in the plate over the allograft should not be filled. The allograft is harder and more brittle than the patient’s own bone and, as a result, screw insertion into the allograft can be associated with fracture. As discussed in the previous section, another option for fixation of the intercalary allograft is intramedullary fixation. Intramedullary fixation devices have the advantage of spanning the host-allograft junctions proximally and distally, not creating holes in the allograft, and intramedullary structural support even when the graft has healed (Fig. 4). The disadvantage of intramedullary fixation is the lack of rigid compression at the host-allograft junction sites. The combination of plate fixation and intramedullary fixation is an attractive compromise that allows stabilization of
the entire bony construct with the intramedullary device and rigid fixation and compression at the host-allograft junctions with plate osteosynthesis. Screws can be placed at oblique angles to avoid the intramedullary device. The advent of locking plates alleviates the need for oblique screws; unicortical locking screws provide rigid fixation and compression across the host-allograft junction. Some clinicians recommended the augmentation of the host-allograft junction with a vascularized fibula to facilitate union. This is especially helpful when the patient is receiving chemotherapy which can result in delayed bone healing.
Intercalary Autograft Autogenous strut bone graft is another reconstructive option for diaphyseal defects. Nonvascularized strut autografts have been used successfully to reconstruct intercalary defects up to 8 cm in length; however, vascularized autografts are advocated for the reconstruction of longer defects. Vascularized fibular reconstruction for segmental bone defects has been used in both lower and upper extremity reconstructions. Although some clinicians advocate vascularized fibula reconstruction for tibia defects in children, due to the small diameter of the fibula and lack of structural integrity, vascularized fibulas may be better suited for upper extremity reconstructions. When used in the lower extremity, the incidence of fracture is significant unless the extremity is protected. In the past, some clinicians have recommended dual fibular grafts for lower extremity lesions and single fibular grafts for the
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Figure 6 (A) Intraoperative photo of humeral diaphyseal resection. (B) Intraoperative photo of humeral diaphyseal reconstruction with metal intercalary spacer. (C) AP radiograph of the humeral metal intercalary spacer. (Color version of figure is available online.)
upper extremity.11,12 However, it has been shown that single vascularized fibular autografts undergo significant hypertrophy within 12 months of the reconstruction and thus may make dual fibular grafting unnecessary. Fixation of the fibular autograft can be achieved by plate or bicortical screw fixation. For short segments, a single compression plate can bridge both proximal and distal host-autograft junctions and is sufficient. Two plates may be needed for longer intercalary segments. To avoid the creation of a stress riser, the two plates should overlap by at least four screw holes. When the fibula can securely fit with the medullary canal of the resection defect, the graft can be secured proximally and distally with bicortical screws. A microvascular surgical team is needed for the vascular anastamosis, and the team should be consulted before initiating the procedure. The fixation of the graft should be completed before the microvascular reconstruction.
Endoprosthetic Replacement Diaphyseal defects can also be reconstructed with an intercalary metal spacer.13-15 The intercalary metal spacer offers the advantage of immediate stable fixation and hence immediate weight bearing. However, intercalary metal spacers have several drawbacks: limited stem length selection, the need for overdistraction to engage the male and female segments in the femoral version of the component, and a high failure rate
due to loosening of the prosthesis.13,16 This reconstruction technique has a limited life span and thus is only warranted in elderly patients, those patients with metastatic disease, or when a biologic reconstructive option is not available. The diaphyseal lesion should be resected as described above. Rotation should be marked, as previously described, with anterior cortical marks before removing the specimen from the resection bed. The resected specimen should be measured on the back table and an intercalary endoprosthetic device of similar length is constructed. In the past, intercalary metal spacers were custom. However, Stryker Orthopaedics (Mahwah, NJ) presently offers modular intercalary spacers so that the desired spacer length can be constructed intraoperatively. The stems of the intercalary spacers must be cemented. The canals should be prepared in the standard fashion by sequential reaming and each stem is cemented separately. Rotational alignment of each segment and the diaphysis is maintained by lining up the prosthesis and the anterior cortical marks made before resection of the specimen. In the femur, each segment of the intercalary spacer links to the next via a standard morse taper and complete assembly requires overdistraction of the segments to engage the morse taper (Fig. 5). In the humerus, the segments are not linked by a morse taper but are joined side-to-side and locked with a locking bolt (Fig. 6).
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Postoperative Rehabilitation For diaphyseal resections and reconstructions, the aim is early motion at the adjacent joints. All reconstructions should be of sufficient strength to allow immediate motion of the joints proximal and distal to the reconstruction. For intercalary reconstruction with allograft or autograft, the patient is non-weight bearing until radiographs demonstrate union at the host-graft junction. Muscular strength can be maintained with isometric exercises. The patient can fully weight bear once healing is demonstrated on the radiographs, 6 to 12 months postoperative. As stated previously, early weight bearing is permitted for endoprosthetic (metal spacer) reconstructions and intramedullary stabilization with PMMA.
3.
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5. 6.
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8.
9.
Summary Diaphyseal reconstruction of long bones following tumor resection can involve a variety of different surgical techniques. The technique used should be individualized on a case-bycase basis. In all cases, the oncological outcome is of paramount importance and should not be compromised. When used appropriately, the techniques described above allow surgical resection and limb-preserving reconstruction that restores satisfactory function.
10. 11. 12.
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References 1. Lewis VO, Gebhardt MC, Springfield DS: Parosteal osteosarcoma of the posterior aspect of the distal part of the femur. Oncological and functional results following a new resection technique. J Bone Joint Surg Am 82A:1083-1088, 2000 2. Harrington KD, Sim FH, Enis JE, et al: Methylmethacrylate as an adjunct in internal fixation of pathological fractures. Experience with
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three hundred and seventy-five cases. J Bone Joint Surg Am 58:1047-1055, 1976 Mankin HJ, Doppelt SH, Sullivan TR, et al: Osteoarticular and intercalary allograft transplantation in the management of malignant tumors of bone. Cancer 50:613-630, 1982 Mankin HJ, Gebhardt MC, Jennings LC, et al: Long-term results of allograft replacement in the management of bone tumors. Clin Orthop 324:86-97, 1996 Mankin HJ, Springfield DS, Gebhardt MC, et al: Current status of allografting for bone tumors. Orthopedics 15:1147-1154, 1992 Muscolo DL, Ayerza MA, Aponte-Tinao L, et al: Intercalary femur and tibia segmental allografts provide an acceptable alternative in reconstructing tumor resections. Clin Orthop 426:97-102, 2004 Berrey BH Jr, Lord CF, Gebhardt MC, et al: Fractures of allografts. Frequency, treatment, and end-results. J Bone Joint Surg Am 72:825833, 1990 Lord CF, Gebhardt MC, Tomford WW, et al: Infection in bone allografts. Incidence, nature, and treatment. J Bone Joint Surg Am 70:369376, 1988 Gerrand CH, Griffin AM, Davis AM, et al: Large segment allograft survival is improved with intramedullary cement. J Surg Oncol 84:198208, 2003 Simon MA, Springfield D (eds): Surgery for Bone and Soft-Tissue Tumors. New York, NY, Lippincott-Raven, 1998 Jupiter JB, Ring D: Operative treatment of post-traumatic proximal radioulnar synostosis. J Bone Joint Surg Am 80:248-257, 1998 Mohler DG, Yaszay B, Hong R, et al: Intercalary tibial allografts following tumor resection: The role of fibular centralization. Orthopedics 26:631-637, 2003 Abudu A, Carter SR, Grimer RJ: The outcome and functional results of diaphyseal endoprostheses after tumour excision. J Bone Joint Surg Br 78:652-657, 1996 Heck DA, Chao EY, Sim FH, et al: Titanium fibermetal segmental replacement prostheses. A radiographic analysis and review of current status. Clin Orthop 204:266-285, 1986 Kuo KN, Gitelis S, Sim FH, et al: Segmental replacement of long bones using titanium fiber metal composite following tumor resection. Clin Orthop 176:108-114, 1983 Damron TA, Sim FH, Shives TC, et al: Intercalary spacers in the treatment of segmentally destructive diaphyseal humeral lesions in disseminated malignancies. Clin Orthop 324:233-243, 1996