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Vol 11, No 2, March/April 2003 109 Osteoporosis is a systemic disease characterized by decreased bone mass and deteriorated bone microar- chitecture. In the elderly (≥65 years), it is a contributing factor in 75% of fractures caused by low-energy falls. 1 Fractures resulting from osteoporosis generally involve the metaphyseal regions of the skeleton. These regions are affected earlier and more profoundly during the development of osteoporosis because they are composed mostly of cancellous bone, which has a greater surface area for bone turnover compared with the compact cortical bone of the diaphysis. In the United States, 1.5 million fractures are reported annually, most from low-energy falls, includ- ing 300,000 proximal femur fractures, 250,000 distal radius fractures, and 300,000 fractures in other bones affected by osteoporosis. Of the 28 million Americans with osteoporosis, 80% are women. Fifty percent of women and 18% of men older than 50 years will sustain an osteoporotic fracture. 1 Although $13.8 billion is spent annually to manage these fractures, <50% of hip fracture patients recover fully after treatment. 2,3 These statistics emphasize the need for skilled fracture care for osteoporotic patients. Reasonable return of function in the elderly requires solid internal fixation and rapid initiation of rehabilitation. Conversely, inadequate fixation or prolonged immobilization with nonsurgical care increases the risk of thromboembolic disease, pul- monary complications, decubitus ulceration, and generalized muscu- loskeletal deterioration from which complete recovery is unlikely. Achieving stable internal fixation for fractures in osteoporotic bone can be problematic but is central to effective care. Fracture Management in Osteoporotic Patients The goal of definitive fracture care in elderly patients is early restoration of function. Treatment should be timely; generally, these patients are in the best condition to undergo surgery within the first 48 hours after injury. 4,5 Nevertheless, the presence of concurrent illness requires thorough evaluation before surgery. Preoperative management to optimize the patient’s condition or correct any decompensation resulting from the injury can benefit survival. 5 Procedures should be kept as simple as possible to minimize surgical time, blood loss, and physiologic stress. Early weight bearing is possible only after successful stable fracture fixation in the lower extremity. Although anatomic restoration is important for intra- articular fractures, metaphyseal Dr. Cornell is Associate Attending Ortho- paedic Surgeon, Hospital for Special Surgery, New York, NY. Reprint requests: Dr. Cornell, 535 East 70th Street, New York, NY 10021. Copyright 2003 by the American Academy of Orthopaedic Surgeons. Abstract Because of the decreased holding power of plate-and-screw fixation in osteoporotic bone fractures, internal fixation can have a high failure rate, ranging from 10% to 25%. Screws placed into cortical bone have better resistance to pullout than do those placed into adjacent trabecular bone. Plates should not be used to bridge unstable regions of bony comminution in osteoporotic patients. Fixation stability is optimized by securing stable bone contact across the fracture site and by placing screws both as close to and as far from the fracture as possible. Intentional shortening can improve stability and load sharing of the fracture construct. Structural bone graft or other types of fillers can be used to fill voids when comminution prevents stable contact. Load-sharing fixation devices such as the sliding hip screw, intramedullary nail, antiglide plate, and tension band constructs are better alternatives for osteoporotic metaphyseal locations. Proper planning is essential for improved fracture fixation in this high-risk patient group. J Am Acad Orthop Surg 2003;11:109-119 Internal Fracture Fixation in Patients With Osteoporosis Charles N. Cornell, MD and diaphyseal fractures are best managed by attempts to primarily achieve stability rather than anatomic reduction. Appropriate treatment of fractures secondary to osteoporosis requires understanding the effect of the disease on the material and structural properties of bone, as well as any effect on the process of fracture healing. Decline in the capacity for fracture repair is age related. 6 Disturbance of the development of strength within fracture callus in the elderly has been shown in experimental rat models, 7 but little is known about the causes of osteoporosis and its effect on the fracture repair process in humans. 8 None- theless, impaired fracture healing in osteoporotic patients is assumed. The principles of biologic fracture repair should be applied whenever possible. 9 Careful handling of the surrounding soft tissues and avoid- ing unnecessary stripping of fracture fragments preserve blood supply to the fracture site. Minimizing exposure of the fracture with preserva- tion of the fracture hematoma may speed development of callus. Bone failure, not implant break- age, is the primary mode of failure of internal fixation in osteoporotic bone. Because bone mineral density correlates with the holding power of screws, osteoporotic bone often lacks the strength to hold plates and screws securely. 10-12 Furthermore, comminution can be severe in osteoporotic fractures. Surgical treatment of fractures of the proximal humerus, proximal and distal femur, and proximal tibia has resulted in an increased incidence of poor results in elderly, osteoporotic patients. In proximal humerus fractures in elderly patients, more than 50% have fair or poor results because of screw loosening and pullout from the humeral head. 13 Internal fixation of intertrochanteric fractures fails in 10% of cases because of cutout of the lag screw from the cancellous bone of the femoral head. 14 Although open reduction and internal fixation yields results superior to those of nonsurgical management for supracondylar femur fractures, 25% of patients treated with the angled blade plate have fair to poor results because of loss of reduction caused by loosening of the implant in the osteoporotic bone of the femoral condyles. 15,16 Traditional internal fixation techniques must be modified to achieve satisfactory results in osteoporotic bone. Internal fixation devices that allow load sharing with host bone should be used to minimize stress at the bone-implant interface. Sliding nail plate devices, intramedullary nails, antiglide plates, and tension band constructs are better than more rigid techniques to treat osteoporotic bone fracture. Implant Fixation in Osteoporotic Bone Screws Resistance to pullout of a screw placed in bone depends on the length of the screw purchase, thread diameter, and quality of the bone into which it is inserted. Recent studies also have indicated that the trabecular orientation within the bone is important. Bone is highly anisotropic. Screws placed parallel to the trabecular pattern have greater pullout strength than do those placed across the trabeculae. 17 The variable of bone quality becomes the prime determinant of screw holding power in osteoporotic bone. 17,18 When bone mineral content falls below 0.4 gm/cm 2 , the effect of varying thread diameter is lost. 18 Therefore, a plan to place screws into osteoporotic bone should be designed to place them as parallel as possible to the cancellous trabeculae. Also, the screws should have the largest thread diameter compatible with the scale of the fracture being repaired. Most importantly, if possible, screws should be placed to secure fixation into cortical bone. Cortical bone has greater mineral density and, therefore, greater resistance to screw pullout than does the adjacent trabecular bone. Thus, in poor quality bone, a smaller diameter cortical screw may be better than a larger diameter cancellous screw that does not secure cortical purchase. In cases of severe osteoporosis, screw fixation may be augmented with polymethylmethacrylate (PMMA). 16,19,20 Although PMMA has relatively poor adhesion to bone, its intrusion into the cancellous structure results in a much stronger composite after the cement polymerizes. One screw fixation augmentation technique 21 begins with removal of any screws that have inadequate purchase or have stripped with tightening. The PMMA powder and liquid should be cooled to slow polymerization. Once the components are mixed, the liquid cement is placed into a 10-mL syringe with the tip widened by drilling it out with a 3.5-mm drill. The cement then can be in- jected into the stripped screw holes, and the screws replaced but incom- pletely tightened. The screws are fully tightened once the cement has set. (Manipulation of the screw while the cement is setting loosens the bond between the cement, bone, and screw, lowering the pullout strength.) Struhl et al 19 described an alternative method similar to cement techniques used for fixation of intramedullary prostheses. The medullary canal is blocked proximal and/or distal to the fracture site, and the entire medullary cavity is filled with cement. After the fracture is reduced and the cement has cured, the screws are inserted by drilling and tapping. Screws placed during the curing process are tightened once the cement has cured. This technique is very useful when Internal Fracture Fixation in Patients With Osteoporosis Journal of the American Academy of Orthopaedic Surgeons 110 poor screw fixation is combined with significant bone loss. Plates The strength of plate fixation is directly affected by the degree of comminution and the resulting size of any gap at the fracture site. In addition, the pattern of screw placement influences the strain experienced within the plate and its screws. 22,23 The most important factor that reduces strain in plated fractures is the degree to which cortical contact can be achieved at the fracture site. Experimental fractures stabilized by plates spanning a gap had three times the strain of fractures stabilized with secure cortical contact. 23 Additionally, for a given fracture pattern, the screw spacing is more important than the number of screws used for fixation. 22 Strain within a plated construct is least when screws are placed both as close to and as far from the fracture site as possible. In two-part fractures or those with solid cortical contact, the farther the screws are placed from the fracture, the less the strain experienced within the plate. Thus, in longer plates with screws placed as close to and as far as possible from the fracture site, intervening screws add little to overall fixation strength. In comminuted fractures or those with a gap, the longer plate retains its advantage, but an increased number of screws adjacent to the fracture site reduces the strain within the plate. Ellis et al 23 concluded that three screws should be placed in the holes adjacent to either side of the fracture gap as well as the most distant hole of the plate, since additional intervening screws add little to the load experienced by the plate. Longer plates with widely spaced screws should be used in osteoporotic bone. Cortical contact at the fracture site is paramount; if moderate areas of comminution exist, the fracture should be shortened to achieve contact, especially in the cortex opposite the plate. 15,16 Plates should not be used to bridge gaps in osteoporotic bone but should be used as tension bands, which require an intact, load- sharing cortex opposite the plate. When comminution is extensive and prevents stable contact opposite the plate, double-plating should be con- sidered to secure stability. In addition, the plates should be placed to act as antiglide plates whenever possible, especially in short oblique or spiral oblique fracture patterns. In such situations, the plate can be positioned to create an axilla with the cortex at the apex of the oblique tongue of the fracture (Fig. 1). The plate position acts to prevent fracture displacement, placing less importance on screw fixation within the weak, adjacent metaphyseal bone. It also positions the plate for insertion of lag screws, which are important to treat the oblique fracture pattern. Intramedullary Nails Intramedullary nail fixation is well suited for diaphyseal fractures in osteoporotic bone and is the treatment of choice for diaphyseal fractures of the femur and tibia. 24 The nails provide broad areas of purchase, allow load sharing, and offer sufficiently secure fixation to allow immediate weight bearing in many circumstances. 25 The development of interlocking nails has extended the indications for intramedullary nailing to include metaphyseal fractures. Intramedullary nails are positioned closer to the mechanical axis Charles N. Cornell, MD Vol 11, No 2, March/April 2003 111 Figure 1 The antiglide fixation method. A, Direction of the fracture displacement (arrow). B, The plate is positioned to create an axilla at the apex of the fracture, and the distal fragment reduces into the axilla. The arrows indicate the corrective force exerted by the plate. C, The plate minimizes the tendency for displacement and achieves compression along the fracture line (arrows). Strong screw fixation in the diaphysis of the proximal fragment holds the reduction (arrows) and makes the distal screws unnecessary. Placement of the plate in the plane of the fracture obliquity makes it easy to place a lag screw through the plate. (Adapted with permission from Carr JB, Trafton PG: Malleolar fractures and soft tissue injuries of the ankle, in Browner BB, Jupiter JB, Levine AM, Trafton PG [eds]: Skeletal Trauma, ed 2. Philadelphia, PA: WB Saunders, 1998, vol 2, pp 2327-2404.) A B C of the bone and, as a result, are sub- ject to smaller bending forces than are plated constructs placed on the external surface of the bone. Fa- tigue failure is less likely with intramedullary nails than with plate constructs. Mechanically locked intramedullary nails provide greater strength in axial loading than do condylar blade plates but are markedly less stable during bending and torsion when used in the distal femur. 26,27 Thus, although locked nails provide less stability than do condylar blade plates in simple, metaphyseal fractures, they are better suited for fixation of severely comminuted osteoporotic bone fractures with no reconstructable medial buttress. The major weakness of locked intramedullary nails is the security of the locking screws, which may loosen in osteoporotic metaphyseal bone. This is particularly likely in the bone of the distal femur and can lead to loss of control of the distal fragment, which often results in ro- tational and varus/valgus malalign- ment. Locking screw fixation can be improved by using different planes of screw orientation (eg, anteroposterior and transverse placement), 28 by using osteoporotic nuts and washers on the medial side of the femur where the locking bolts emerge, or by using cement to improve fixation. 16 Tension Band Wiring Tension band wiring is usually applied to transverse fractures, which are distracted by the pull of attached tendons and ligaments. This technique provides strong and secure fixation, which allows immediate mobilization of involved joints. Fractures of the olecranon and patella can be successfully treated with this method. The tension band wire has additional advantages in osteoporotic bone. In metaphyseal locations, such as the proximal humerus or medial malleolus, tendon and ligament insertions to bone can provide better strength for fixation than does the bone itself. In these areas, placement of tension band wires within the soft-tissue attachments can provide excellent anchorage. Hawkins et al 29 reported better clinical results with tension band wiring than with plate- and-screw fixation in proximal humerus fractures. A similar technique can be used to secure extremely osteoporotic or comminuted medial malleolar fractures (Fig. 2). The fracture is reduced and main- tained with small Kirschner wires. The tension band wire is passed within the fibers of the deltoid ligament and proximally secured to bone by passing it around a screw placed through the tibia. The wire is placed in figure-of-8 fashion and can be tightened by opposing twists. Tension band wires also can supple- ment plate-and-screw fixation in fractures that may be subjected to tensile loading. After securing the fracture with plate and screws, a tension band wire is passed within adjacent tendinous attachments and beneath the plate to help neutralize tensile forces across the construct (Fig. 3). Augmentation Bone grafting plays several important roles in the treatment of osteoporotic fractures. Cancellous bone graft can be used to augment or encourage rapid fracture healing. Cancellous bone is osteoinductive, osteoconductive, and osteogenic, 30 and it can stimulate new bone for- mation periosteally in fracture gaps created by comminution. There is no evidence that osteoporotic bone is an inferior graft material. Corticocancellous bone graft can be used in osteoporotic fractures to replace regions of skeletal loss caused by comminution or crush, thus enhancing fracture construct stability. This is especially true for metaphyseal and joint depression fractures, such as split-depression tibial plateau fractures, intra-articular fractures of the distal radius, distal humerus fractures, and tibial plafond fractures. Surgical repair requires elevation of the articular surface to restore joint congruity with the use of structural bone graft to fill in the metaphyseal void and provide support to the subchondral region. The iliac crest is the most common donor site for autogenous bone graft. The morbidity associated with the harvest of autogenous bone is a concern, 31 especially in the Internal Fracture Fixation in Patients With Osteoporosis Journal of the American Academy of Orthopaedic Surgeons 112 Figure 2 Tension band wiring. Kirschner wires are placed to hold the medial malleolus fracture reduced. A figure-of-8 wire is then passed distal to the wires through the substance of the deltoid ligament and anchored to a screw placed proximal to the fracture. (Adapted with permission from Carr JB, Trafton PG, Simpson LA: Fractures and soft tissue injuries of the ankle, in Browner BD, Jupiter JB, Levine AM, Trafton PG [eds]: Skeletal Trauma, ed 2. Philadelphia, PA: WB Saunders, 1998, vol 2, pp 1871-1957.) elderly. In older osteoporotic individuals, the quantity and quality of bone available at the iliac crest is often insufficient, requiring a larger exposure, which increases the risk of donor site complications. Bone graft substitutes can provide an at- tractive alternative to autograft in osteoporotic patients. 32 Bone graft substitutes include allograft bone, demineralized allograft bone products, and synthetic osteoconductive materials, which can be used as bone void fillers. Several of these products have been shown to be essentially equivalent to autogenous graft for treatment of acute fractures. 33,34 Replacement of severely comminuted areas with PMMA to re- gain stablility is sometimes required after severe skeletal loss. It has been used successfully, especially in supracondylar fractures of the femur 16,19 and intertrochanteric fractures. However, PMMA is not an ideal material for this purpose because it is a permanent implant and a foreign body within bone. It also generates considerable heat with polymerization, which may be harmful to bone and surrounding soft tissue. Cements made from calcium phosphate adhere better to bone and have the advantage of being resorbed and replaced by host bone. These cements are not used to augment screw fixation but to fill voids caused by comminution or severe osteoporosis. Calcium phosphate cements have been useful in intertrochanteric and distal radius fractures. 35,36 These new cements can provide enough support to allow earlier load bearing and decrease the dependency on internal fixation devices. PMMA can be used to augment screw purchase in the severely osteoporotic diaphysis, but another useful approach is to place an augmentation device into the medullary canal to incorporate as bone or be resorbed. Fibular allograft struts are used for this purpose (Fig. 4). The fibular strut improves local bone stock for screw purchase and can be incorporated to provide a span across regions of diaphyseal deficiency. Creative strategies such as these can be extremely successful for treating osteoporotic diaphyseal fracture and nonunion. Fracture Types Intertrochanteric Fractures The sliding hip screw (SHS) has markedly advanced the treatment of intertrochanteric fractures. 37,38 The success of the SHS is based on its design, and in many ways it is the ideal device for this typically osteoporotic fracture. The SHS has a lag screw that gains broad purchase in the highest quality bone in the femoral head. The dynamic slide of the lag screw and side plate allows impaction at the fracture site with load sharing along the plane of the fracture. The success of load sharing is evident in that the length of the side plate makes little difference in the stability of an SHS construct. 39 When the SHS is inserted correctly, in all but the most unstable fractures the failure rate of fixation is <5%, even in extremely osteoporotic patients. 14,40 The most important aspect of SHS insertion is to ensure that the lag screw is placed in the center of the femoral head (within 10 mm of the femoral head apex in both the anteroposterior and lateral radiographic views). Charles N. Cornell, MD Vol 11, No 2, March/April 2003 113 Figure 3 Anteroposterior radiograph of a tension band wire augmenting plate fixation in the proximal humerus. The wire is passed in figure-of-8 fashion beneath the supraspinatus tendon and distally beneath the plate (arrow). The wire provides a strong purchase and acts to neutralize the deforming pull of the rotator cuff. Figure 4 Anteroposterior radiograph of a repair of a humeral nonunion with seg- mental bone loss. A fibular strut allograft was fashioned into an intramedullary peg. It spanned the defect and improved the screw purchase proximal and distal to the fracture site. The loose distal screw was hidden within soft tissues left from a prior attempt at reconstruction. Additionally, the lag screw must be able to slide within the side plate barrel to allow stable impaction at the fracture site. To this end, the side plate angle should be ≥135°. With a short lag screw, a short-barrel plate should be used to assure adequate slide. Generally, a short- barrel side plate should be used when the lag screw is <85 mm. The surgeon should ensure that 10 mm of slide can occur. Unfortunately, similar success does not occur with unstable four- part fractures, reverse obliquity fractures, or fractures with subtrochanteric extension because the lack of a lateral buttress and the loss of the posteromedial bone for load sharing prevents them from dynam- ically achieving stability. 41 As a result, the SHS allows maximum medial displacement of the shaft, leading to either unacceptable shortening at the fracture site or cutout of the lag screw from the femoral head because the lag screw threads have come to rest on the barrel of the side plate (Fig. 5). In these unstable fracture patterns, devices are needed to recreate a lateral buttress or allow vertical, dynamic impaction. Fixed- angle devices such as the 95° condylar screw can be used. 42 This type of device provides a lateral buttress, but because it has a fixed angle, it cannot load-share unless an intact medial buttress can be reconstituted. Failure is almost guaranteed without this medial support opposite the plate (Fig. 6). Additionally, these devices do not allow weight bearing immediately after surgery. Alternative devices for treating unstable peritrochanteric fracture include the intramedullary hip screw (Gamma nail) and vertically sliding plate. The intramedullary SHS provides the advantages of an intramedullary nail combined with a dynamic hip screw that allows impaction of the peritrochanteric fracture. 25,43 The intramedullary position decreases the lever-arm on the device and creates its own lateral buttress that prevents excessive lateral migration of the proximal fragment. The strength of the device allows immediate weight bearing. Use of the long intramedullary nail helps avoid fracture of the femoral shaft that can occur when the short Gamma nail is used. The insertion of intramedullary hip screws can be technically demanding because the fracture must be reduced before reaming and nail insertion to avoid comminution of the fracture site and adjacent cortex. Open reduction before nailing is recommended unless a nearly perfect closed reduction can be achieved. The vertical SHS allows fractures to impact without excessive lateral displacement (Fig. 7). Although clinical experience with these devices is preliminary, initial results are encouraging. 44 The primary advantages of this device are the ease with which it can be inserted as well as its use to salvage an SHS that has been complicated by lateral cortex comminution during insertion. Supracondylar Fractures of the Distal Femur Osteoporosis weakens the supracondylar region of the distal femur in the elderly, allowing even low-energy injuries to result in complex fractures. Intra-articular involvement and comminution of the metaphysis is common in this population. The chal- Internal Fracture Fixation in Patients With Osteoporosis Journal of the American Academy of Orthopaedic Surgeons 114 Figure 5 Anteroposterior radiograph of a reverse obliquity fracture pattern. A sliding hip screw was used to stabilize the fracture, which lacks a stable lateral buttress. Without a lateral buttress, the dynamic slide of the plate could not achieve stability. The proximal fragment displaced until no further slide could occur, so the dynamic hip screw became a fixed-angle, load-bearing device. As a result, the lag screw cut out of the femoral head. Figure 6 Anteroposterior radiograph of a subtrochanteric fracture treated with a 95° dynamic condylar screw plate. A defect in the medial cortex persisted after reconstruction. The plate acted as a bridge plate rather than a tension band, which resulted in loosening of the screws of the side plate, with loss of reduction of the fracture. lenge of treating these fractures led to the development of closed treatment methods using traction and cast bracing, but those techniques resulted in loss of range of motion. The development of internal fixation methods for these fractures has allowed restoration of anatomy and early knee rehabilitation. Many features make the 95° blade plate designed for supracondylar fractures ideal for fixation in osteoporotic bone. Retrograde intramedullary nails do not provide the same stability as do the 95° devices 26,27,45 and should be re- served for fractures around total knee replacements, 46 those with severe comminution into the diaphysis, or those with severe skin compromise around the knee. The 95° condylar screw was designed to make insertion of the device easier compared with the blade plate. However, it sacrifices more bone from the distal femur with insertion and cannot be as easily revised. It is also slightly larger and can impinge on the lateral soft tissues of the knee. In contrast, the blade plate is low profile and requires very little bone sacrifice; also, the position of the blade can be revised without compromising fixation. However, the blade plate is more technically demanding to insert. Although the blade plate can be used successfully as a bridging plate in younger individuals with good bone stock, it should be used only as a tension band in the elderly. This requires reconstitution of a load-sharing medial femoral cortex opposite the blade plate. For many fractures, this can be accomplished by shortening the fracture into a position of stability by impacting the fracture surfaces. Shortening of as much as 1 to 2 cm can be done without notable loss of function. 15 Healing is usually rapid after shortening because the comminuted medial bone functions as bone graft. 16 In severely comminuted fractures in which sufficient stability cannot be accomplished by shortening, the surgeon can resort to double plating the distal femur 47 or replacing the region of bone loss with cement. Lateral Tibial Plateau Fractures The split-depression or Schatzker type II (AO classifications B2 and B3) is the most common lateral tibial plateau fracture in the osteoporotic patient. Fractures with <5 mm of joint surface depression in a patient with a knee that is stable to varus/ valgus stress can be managed nonsurgically. Surgical reconstruction is required if the degree of joint depression is >5 mm and if there is >5° of varus/valgus instability. The surgical technique for repair of the split-depression lateral tibial plateau fracture has been reported extensively. 47,48 Benirschke et al 49 suggested modifications of this technique that call for use of a small fragment plate specifically designed for the lateral tibial plateau. The small fragment plate is low profile and allows placement of proximal screws very close to the subchondral plate of the reduced tibial plateau. As many as four screws can be inserted, providing extensive support of the reduced joint surface. The small screws can be placed into opposing cortex to secure cortical purchase without the risk of soft-tissue irritation associated with pro- truding large fragment cancellous screws. Because the screws placed under the subchondral bone are reminiscent of rafters supporting a roof or a floor, this has been referred to as the rafter plate technique (Fig. 8). This modification of the standard technique is useful for the osteoporotic patient. 49 Insertion of a bone graft to fill the metaphyseal defect created after elevation of the joint surface is standard, but substitution of other osteoconductive materials, such as calcium phosphate cements and hydroxy- Charles N. Cornell, MD Vol 11, No 2, March/April 2003 115 Figure 7 Anteroposterior radiograph of a sliding hip screw with vertical slide capa- bility. This plate was chosen after attempt- ed insertion of a standard side plate resulted in comminution of the lateral cortex around the lag screw insertion site. The vertical slide allows axial settling in this unstable fracture pattern. Stable bone contact is achieved without excessive lateral displacement of the head and neck. Figure 8 The rafter plate technique. Four 3.5-mm screws are inserted through a cus- tom plate and placed close to the subchondral plate, providing a broad area of support. (Adapted with permission from Benirschke SK, Swiontkowski MF: Knee, in Hansen ST Jr, Swiontkowski MF [eds]: Orthopaedic Trauma Protocols. New York, NY: Raven Press, 1993, pp 291-329.) apatite implants, has proved to be successful. 33 Ankle Fractures and the Distal Fibula Ankle and foot fractures are among the most common fractures sustained by women, and most ankle fractures occur in women aged 75 to 84 years. The prognosis for ankle fractures is worse in the elderly than in younger individuals, but the treatment principles are identical. 50 Even small amounts of residual displacement in the mortise markedly alter the load-bearing distribution on the talus, leading to poor clinical out- comes. 51,52 As in younger patients, ankle fractures must be treated with anatomic reduction until healing. Isolated fractures of the lateral malleolus without injury to the medial malleolus or deltoid ligament can be treated nonsurgically, whereas unstable ankle fractures require open reduction and internal fixation. Surgical fixation of the ankle in the elderly can be made more difficult by poor skin integ- rity, swelling, diabetes, and vascular disease. In addition, bone loss from an osteoporotic lateral malleolus can compromise the ability to secure internal fixation of the lateral aspect of the ankle. Most lateral malleolar fractures are short oblique or spiral oblique patterns, with the apex of the fracture posterior and proximal. The most accepted fixation technique is placement of a plate on the lateral surface of the malleolus through a lateral incision. Modifying this technique by placing the plate on the posterior surface of the fibula puts it in the antiglide position, which results in superior biomechanical performance 53 (Fig. 9). Additionally, with the plate placed posteriorly, the skin incision can be more posterior, allowing for better coverage of the fibula if wound- healing problems occur. The best advantage of the antiglide position is that the purchase of the distal screws is relatively unimportant; the important screw fixation is in the more proximal cortical region of the fibula. The antiglide principle can be applied to any oblique fracture, especially medial tibial metaphyseal fractures and spiral oblique fractures of the distal tibial metaphysis. Proximal Humerus Fractures Proximal humerus fractures com- monly occur in elderly women; for- tunately, 80% of these fractures are impacted or minimally displaced and heal with a brief period of immobilization. Unstable fractures displace because of the pull of the musculature attached to the upper humerus. If not reduced, they will result in malunion, with loss of range of motion, strength, and function of the shoulder girdle. Loss of shoulder motion can diminish the ability to dress and attend to per- sonal hygiene. Poor functional outcome after a proximal humerus fracture in the elderly can markedly reduce social independence. Open reduction and internal fixation of unstable two- and three- part fractures of the humerus leading to improved functional outcome is ad- vantageous in the elderly. Repair of proximal humerus fractures is extremely challenging, and results are often disappointing even with experienced surgeons. Pros- thetic replacement of the humeral head is indicated in three- or four- part fractures in which the head is only a deficient shell of subchondral bone. However, functional results of two- and three-part fractures are better if open reduction and preser- vation of the humeral head can be done. 29 Plating of the proximal humerus is often unsatisfactory because of poor screw purchase and acromial impingement caused by the bulkiness of the hardware. 13,54 Hawkins et al 29 first described the advantage of tension band fixation for such fractures after recognizing that the tendinous attachment of the rotator cuff to the tuberosities provides excellent purchase for figure- of-8 wires. The tendon provides better anchorage than does the soft bone of the humeral head, and the reduced bulkiness of wire constructs makes tension band fixation ideal for this region. Excellent clinical results are possible with modifications of Hawkins’ original technique, which involves exposure of the fracture site through an extended deltopectoral approach. 54-56 The fracture is mobilized and the head and shaft are impacted to achieve stability along the fracture site. Intramedullary nails or a simple lag screw can be placed to provide initial stability while the tension band wires are positioned. One is placed under the rotator cuff tendons, and a second can be used to wire the tuberosities together. The wires are attached to the shaft through a drill hole placed lateral through the shaft (Fig. 10). The stability of this construct allows immediate shoulder rehabilitation, thereby optimizing outcome. Extensive metaphyseal comminution, which would lead to excessive shortening with impaction at the fracture site, precludes use of Internal Fracture Fixation in Patients With Osteoporosis Journal of the American Academy of Orthopaedic Surgeons 116 Figure 9 Lateral radiograph of a lateral malleolar fracture stabilized with a plate placed in the posterior or antiglide position. this technique alone. Such shortening can cause subluxation of the shoulder because of laxity in the deltoid muscle. In these cases, a plate should be used to restore and maintain proper height. A modified cloverleaf plate works well because it is small, can be used to place mul- tiple screws into the head, and can be supplemented with a tension band wire for added support. Re- cently, interlocking proximal humeral nails and blade plates have been advocated for these fractures. Proximal humeral plates with fixed- angle screws also have been intro- duced. Although these devices are promising, clinical experience has yet to be reported. Postoperative Care Postoperative care of patients with osteoporotic fracture should include both physical rehabilitation and psy- chosocial treatment. Many elderly patients have marked preinjury functional compromise, and the additional disability associated with recovery makes short-term rehabilitation necessary for most before eventual return home. Depression and hopelessness are common in the elderly after injury and must be addressed by the health care team. These patients are best treated by a multidisciplinary service in which their medical, psychological, and social concerns are addressed. Many elderly patients enter the hospital in a malnourished state and therefore have a high mortality rate. Malnu- trition results in immunocompro- mise and is associated with higher complication rates for fracture surgery. 57 Clinical evaluation of nutri- tional status can easily be done by assessing the patient’s dietary habits and measuring the serum albumin. A serum albumin <3.5 mg/dL indi- cates chronic protein malnutrition. Elderly patients may have diffi- culty complying with restricted weight bearing after surgery on the lower extremity and should be allowed to bear weight as tolerated with a walker. Because load sharing is the most important principle of osteoporotic fracture surgery, weight bearing as tolerated is not contraindi- cated postoperatively. Most elderly patients will not adhere to partial weight-bearing protocols; therefore, no weight bearing is recommended if there is uncertainty about the stability of the fracture construct. Finally, it should be assumed that any patient past middle age with a low-energy metaphyseal fracture has osteoporosis. These patients should undergo bone mineral density testing and be placed on a regimen to combat further bone loss. They should be encouraged to take calcium 1,000 to 1,500 mg/d with a multivitamin to ensure adequate vi- tamin D intake. Elderly fracture pa- Charles N. Cornell, MD Vol 11, No 2, March/April 2003 117 A C Figure 10 Anterior (A) and lateral (B) views and anteroposterior radiograph (C) of the tension band technique used to treat proximal humerus fractures. A preliminary lag screw impacts the fracture and maintains reduction, then two tension band wires are placed. The first wire is passed beneath the supraspinatus tendon, and the second through the tuberosities. The figure-of-8 wires are passed through a drill hole in the shaft. This construct takes advantage of the strong rotator cuff tendinous insertion and permits immediate postoperative rehabilitation of the shoulder. Wire 1 Wire 1 Wire 2 Wire 2 B tients also should be encouraged to start bisphosphonate therapy because alendronate has been proved to reduce the risk of additional fractures after hip fracture. 58 Treatment of the underlying osteoporosis is part of the fracture treatment. Summary Fracture care techniques often require modification to be useful to treat osteoporotic bone. Screws should be placed into the best-quality-bone available, which is usually an opposing cortex. Screw fixation can be augmented by using PMMA. With plate fixation, stable bone contact at the fracture site is the most important factor for reducing strain in the plate. Shortening of the affected bone can achieve this contact in comminuted fractures. Plates should not be used to bridge areas of comminution in osteoporotic bone and should be as long as possible, with screws placed close to and far from the fracture site. Locked intramedullary nails can be used for diaphyseal fractures or fractures with metaphyseal-diaphyseal comminution. Angled blade plates are very applicable to osteoporotic metaphyseal fractures but should be used as tension band plates that require stable, load-sharing contact opposite the plate. Antiglide plating and use of tension band wires also are effective strategies for osteoporotic fractures. Use of bone graft substitutes is particularly applicable to reduce the morbidity of bone graft harvest and ensure adequate volumes of graft in the elderly. Patients with evidence of osteoporosis should be started on a medical regimen that includes calcium supplementation with a pre- scription for bisphosphonates or other antiresorptive regimes to combat further bone loss. Internal Fracture Fixation in Patients With Osteoporosis Journal of the American Academy of Orthopaedic Surgeons 118 References 1. Lucas TS, Einhorn TA: Osteoporosis: The role of the orthopaedist. J Am Acad Orthop Surg 1993;1:48-56. 2. Egol KA, Koval KJ, Zuckerman JD: Functional recovery following hip fracture in the elderly. J Orthop Trauma 1997;11:594-599. 3. Tinetti ME, Baker DI, Gottschalk M, et al: Home-based multicomponent rehabilitation program for older persons after hip fracture: A randomized trial. Arch Phys Med Rehabil 1999;80:916-922. 4. Aharonoff GB, Koval KJ, Skovron ML, Zuckerman JD: Hip fractures in the elderly: Predictors of one year mortality. J Orthop Trauma 1997;11:162-165. 5. Kenzora JE, McCarthy RE, Lowell JD, Sledge CB: Hip fracture mortality: Relation to age, treatment, preoperative illness, time of surgery, and complications. Clin Orthop 1984;186:45-56. 6. Silver JJ, Einhorn TA: Osteoporosis and aging: Current update. Clin Orthop 1995;316:10-20. 7. Ekeland A, Engesoeter LB, Langeland N: Influence of age on mechanical properties of healing fractures and intact bones in rats. Acta Orthop Scand 1982;53:527-534. 8. Lill CA, Fluegel AK, Schneider E: Sheep model for fracture treatment in osteoporotic bone: A pilot study about different induction regimens. J Orthop Trauma 2000;14:559-566. 9. Mast J, Jakob R, Ganz R (eds): Planning and Reduction Technique in Fracture Surgery. Berlin, Germany: Springer- Verlag, 1989. 10. Sjostedt A, Zetterberg C, Hansson T, Hult E, Ekstrom L: Bone mineral content and fixation strength of femoral neck fractures: A cadaver study. Acta Orthop Scand 1994;65:161-165. 11. Alho A: Mineral and mechanics of bone fragility fractures: A review of fixation methods. Acta Orthop Scand 1993;64:227-232. 12. Strømsøe K, Kok WL, Høiseth A, Alho A: Holding power of the 4.5 mm AO/ASIF cortex screw in cortical bone in relation to bone mineral. Injury 1993;24:656-659. 13. Kristiansen B, Christensen SW: Plate fixation of proximal humeral fractures. Acta Orthop Scand 1986;57:320-323. 14. Baumgaertner MR, Curtin SL, Lindskog DM, Keggi JM: The value of the tip- apex distance in predicting failure of fixation of peritrochanteric fractures of the hip. J Bone Joint Surg Am 1995;77: 1058-1064. 15. Blatter G, König H, Janssen M, Magerl F: Primary femoral shortening osteosynthe- sis in the management of comminuted supracondylar femoral fractures. Arch Orthop Trauma Surg 1994;113:134-137. 16. Schatzker J: Fractures of the distal femur revisited. Clin Orthop 1998;347: 43-56. 17. An YH, Young FA, Kang Q, Williams KR: Effects of cancellous bone structure on screw pullout strength. Medical University of South Carolina Orthopedic Journal 2000;3:22-26. 18. Turner IG, Rice GN: Comparison of bone screw holding strength in healthy bovine and osteoporotic human cancellous bone. Clin Mater 1992;9:105-107. 19. Struhl S, Szporn MN, Cobelli NJ, Sadler AH: Cemented internal fixation for supracondylar femur fractures in osteoporotic patients. J Orthop Trauma 1990; 4:151-157. 20. Motzkin NE, Chao EYS, An K-N, Wikenheiser MA, Lewallen DG: Pull- out strength of screws from polymethylmethacrylate cement. J Bone Joint Surg Br 1994;76:320-323. 21. Helfet DL: Fractures of the distal femur, in Browner BD, Jupiter JB, Levine AM, Trafton PG (eds): Skeletal Trauma: Fractures, Dislocations, Ligamen- tous Injuries. Philadelphia, PA: WB Saunders, 1992, vol 2, pp 1643-1683. 22. Törnkvist H, Hearn TC, Schatzker J: The strength of plate fixation in relation to the number and spacing of bone screws. J Orthop Trauma 1996;10:204-208. 23. Ellis T, Bourgeault CA, Kyle RF: Screw position affects dynamic compression plate strain in an in vitro fracture model. J Orthop Trauma 2001;15:333-337. 24. McConnell T, Court-Brown C, Sar- miento A: Isolated tibial shaft fracture. J Orthop Trauma 2000;14:306-308. 25. Rodriguez Alvarez J, Casteleiro Gon- zolez R, Laguna Aranda R, Ferrer Blanco M, Cuervo Dehesa M: Indica- tions for use of the long Gamma nail. Clin Orthop 1998;350:62-66. 26. Ito K, Grass R, Zwipp H: Internal fixation of supracondylar femoral fractures: Comparative biomechanical performance of the 95-degree blade plate and [...]... and grafting, in Beaty JH (ed): Orthopaedic Knowledge Update 6: Home Study Syllabus Rosemont, IL: American Academy of Orthopaedic Surgeons, 1999, pp 25-35 Younger EM, Chapman MW: Morbidity at bone graft donor sites J Orthop Trauma 1989;3:192-195 Gazdag AR, Lane JM, Glaser D, Forster RA: Alternatives to autogenous bone graft: Efficacy and indications J Am Acad Orthop Surg 1995;3:1-8 Bucholz RW, Carlton... as a bone graft substitute in tibial plateau fractures Clin Orthop 1989;240:53-62 Chapman MW, Bucholz R, Cornell C: Treatment of acute fractures with a collagen-calcium phosphate graft material: A randomized clinical trial J Bone Joint Surg Am 1997;79:495-502 Goodman SB, Bauer TW, Carter D, et al: Norian SRS cement augmentation in hip fracture treatment: Laboratory and initial clinical results Clin... subtrochanteric fractures: A biomechanical study Acta Orthop Scand 1998;69:580-584 44 Lunsjo K, Ceder L, Stigsson L, Hauggaard A: Two-way compression along the shaft and the neck of the femur with the Medoff sliding plate: Oneyear follow-up of 108 intertrochanteric fractures J Bone Joint Surg Br 1996;78: 387-390 45 Koval KJ, Kummer FJ, Bharam S, Chen D, Halder S: Distal femoral fixation: A laboratory... Supracondylar femoral fracture following total knee arthroplasty Clin Orthop 1996;324: 196-209 47 Jazrawi LM, Kummer FJ, Simon JA, et al: New technique for treatment of unstable distal femur fractures by locked double-plating: Case report and 48 49 50 51 52 53 54 55 56 57 58 biomechanical evaluation J Trauma 2000;48:87-92 Tscherne H, Lobenhoffer P: Tibial plateau fractures: Management and expected results Clin... Surg Am 1976;58:356-357 Yablon IG, Heller FG, Shouse L: The key role of the lateral malleolus in displaced fractures of the ankle J Bone Joint Surg Am 1977;59:169-173 Winkler B, Weber BG, Simpson LA: The dorsal antiglide plate in the treatment of Danis-Weber type-B fractures of the distal fibula Clin Orthop 1990; 259:204-209 Szyszkowitz R, Seggl W, Schleifer P, Cundy PJ: Proximal humeral fractures: Management . screw pullout than does the adjacent trabecular bone. Thus, in poor quality bone, a smaller diameter cortical screw may be better than a larger diameter cancellous screw that does not secure cortical. loading than do condylar blade plates but are markedly less stable during bending and torsion when used in the distal femur. 26,27 Thus, although locked nails provide less stability than do condylar. such as the proximal humerus or medial malleolus, tendon and ligament insertions to bone can provide better strength for fixation than does the bone itself. In these areas, placement of tension band

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