Ulna Plate Lateral Placement

Technique of Fracture Fixation Principles of Stable Fixation

As previously indicated, to obtain maximum function the surgeon must achieve anatomical reduction and stable internal fixation. In general, stable internal fixation may be achieved by internal splinting with intramedullary devices or by compression, using plates. In the forearm, intramedullary devices do not control rotational stability and should therefore rarely if ever, be used (Fig. 9.10). Therefore, compression, with interfragmental screws or plates under tension, is the method of choice.

Methods by Fracture Type

Transverse or Short Oblique Fractures. If the fracture of the radius or ulna is either transverse or short and oblique, a plate under tension may be used to com-

Metal Rods Ulnar And Radius

Fig. 9.10a-d. Intermedullary splinting of the radius. a Lateral and b anteroposterior radiographs at 9 months following open reduction and internal fixation of a fracture of both bones of the forearm. The ulna has been plated and has healed, although the distal screw in the plate is loose. The radius was treated with a Rush intermedullary rod and has not united. At this time, the patient had pain on movement and tenderness at the site. The rod was removed and a six-hole dynamic compression (DC) plate applied to this hypertrophic nonunion; the ulnar plate was removed at the same time. c,d Complete bony union 1 year after the second operative procedure

Fig. 9.10a-d. Intermedullary splinting of the radius. a Lateral and b anteroposterior radiographs at 9 months following open reduction and internal fixation of a fracture of both bones of the forearm. The ulna has been plated and has healed, although the distal screw in the plate is loose. The radius was treated with a Rush intermedullary rod and has not united. At this time, the patient had pain on movement and tenderness at the site. The rod was removed and a six-hole dynamic compression (DC) plate applied to this hypertrophic nonunion; the ulnar plate was removed at the same time. c,d Complete bony union 1 year after the second operative procedure press the fracture; i.e., the plate is under tension, the fracture under compression. In the forearm, where exposure is often limited, limited contact dynamic compression (LC-DC) plates should be used wherever possible, making the tension device unnecessary.

The application of a plate under tension in a transverse fracture, if carried out correctly, will afford compression to the fracture, thereby stabilizing it and allowing early motion (Fig. 9.11). The same is true of the short oblique fracture. However, in all cases where the obliquity of the fracture allows, a lag screw should be inserted through the plate across the fracture to increase rotational stability (Fig. 9.12).

Spiral Fractures. For spiral fractures, the obliquity is such that one or two lag screws can be used to obtain anatomical reduction, followed by a neutralization plate. An alternative method is to use two carefully placed cerclage wires with minimal soft tissue dissection, followed by a neutralization plate (Fig. 9.13a-c).

bone has been restored, and the final reduction is achieved, the fracture should be plated without disturbing the soft tissue. If comminution is extensive, then interfragmental compression with lag screws should be used only where fixation of the fragment is essential to ensure anatomical reduction, remembering at all times to preserve the soft tissue attachment to the fragments, if possible. Those fragments with precarious soft tissue attachments, and which are not essential for anatomical reduction, should not be internally fixed.

Once anatomical reduction and interfragmental compression have been achieved, a neutralization plate must be applied to protect the stability of the fracture. Wherever possible, lag screws should be used through the plate and across any of the fracture lines, either in the spiral fracture or in the comminuted fracture, to increase the stability of the system (see Fig. 9.12).

Implant Selection

Comminuted Fractures. Achieving anatomical reduction and preserving the soft tissue attachment to bone in comminuted fractures are more difficult. Indirect reduction techniques, as described, should be used (see Figs. 9.8, 9.13). Once the length of the

For most patients, the 3.5-mm DC or LC-DC plates, with 3.5-mm cortical screws in cortex and 4-mm cancellous screws in the metaphysis are the implants of choice. Occasionally in large patients, the narrow 4.5-mm plates may be used.

Bone Healing Timeline Ulna

Fig. 9.11a-e. Fixation of a transverse fracture with a dynamic compression (DC) plate. a Application of a six-hole DC plate to a fracture of the radius or ulna. b Anteroposterior and c lateral radiographs of a 21-year-old man with a displaced fracture of the radius and a subluxation of the distal radioulnar joint (arrow). d,e Osteosynthesis of this transverse fracture at 1 year. Primary bone union is complete, the functional result excellent

Fig. 9.11a-e. Fixation of a transverse fracture with a dynamic compression (DC) plate. a Application of a six-hole DC plate to a fracture of the radius or ulna. b Anteroposterior and c lateral radiographs of a 21-year-old man with a displaced fracture of the radius and a subluxation of the distal radioulnar joint (arrow). d,e Osteosynthesis of this transverse fracture at 1 year. Primary bone union is complete, the functional result excellent a

The length of the plate will depend on the degree of inherent stability in the fracture, as well as the size of the implant and screws. Therefore, comminuted fractures require longer implants to achieve adequate stability and prevent early mechanical overload and failure. In general, at least six to eight cortices into intact diaphysis are necessary for adequate stability, which in comminuted fractures may require an eight- to 12-hole plate. To achieve maximum stability with the long plates, the screws must be inserted at the ends of the plate and as close to the fracture as possible without interfering with the blood supply (Fig. 9.14).

The 3.5-mm DC plates are not only smaller in width and thickness, but also shorter than their counterparts in the larger DC series; for example, an eight-hole large DC plate is 135 mm long, whereas an eight-hole small DC plate is only 97 mm long, as shown in Fig. 9.15a. Also, the 3.5-mm DC screw has less holding power; therefore, more screws are required to achieve stable fixation (Fig. 9.15b). A new 3.5-mm cortical screw has recently been introduced and is recommended for use with the 3.5-mm DC plate in the forearm. The holding power of the screw is increased by a larger shank (2.7 mm) and more

Fig. 9.12. Application of a lag screw through the plate and across an oblique fracture, wherever possible, to increase the strength of the fixation

Fig. 9.14. For maximum stability with a long plate on a comminuted fracture, the screw holes at the end of the plate as well as those closest to the fracture must be filled

Lag Screw Ulna Radius

Fig. 9.13. a Radiograph of a forearm fracture. Spiral type ulna and transverse comminuted radius. b The ulna was fixed with lag screws and a neutralization plate, the radius with a neutralization plate spanning the comminuted area to preserve its blood supply. c The end result at 18 months is excellent

Fig. 9.13. a Radiograph of a forearm fracture. Spiral type ulna and transverse comminuted radius. b The ulna was fixed with lag screws and a neutralization plate, the radius with a neutralization plate spanning the comminuted area to preserve its blood supply. c The end result at 18 months is excellent

Fig. 9.14. For maximum stability with a long plate on a comminuted fracture, the screw holes at the end of the plate as well as those closest to the fracture must be filled

a threads per length. The instrumentation is characterized by a new 2.5-mm drill. All of the instrumentation has a bronze coloration.

In those instances where small DC plates are chosen, one must be certain that the plate has sufficient length to neutralize the bending forces present and allow firm and rigid immobilization of the fracture. In tall individuals for whom the small 3.5-mm DC plate is chosen, an eight- to 12-hole plate is essential, allowing for the fixation of a minimum of seven cortices on each side of the fracture (see Fig. 9.14). This will provide adequate holding of the plate for a sufficient length of time to allow both early motion of the extremity and sound union of the fracture. Use of the wrong implant may prejudice an otherwise excellent open reduction, as shown in Fig. 9.16, and lead to early failure of the osteosynthesis.

The LC-DC plate has many experimental advantages, especially in open fractures. Since the plate surface is indirect and contact between the plate and the bone is kept to a minimum, loss of blood supply to the cortex is minimized (Fig. 9.17). Most of the cortex remains viable, a marked advantage in open fractures.

Healthy Plate Placement

Fig. 9.15. a An eight-hole 3.5-mm dynamic compression (DC) plate, an eight-hole 4.5-mm DC plate, and a 12-hole 3.5-mm DC plate. Note that the length of the 12-hole 3.5-mm plate is approximately equal to that of the eight-hole 4.5-mm DC plate, whereas the eight-hole 3.5-mm DC plate is much shorter. b A 4.5-mm cortical screw (A), a 3.5-mm cancellous screw (B), and the new 3.5-mm cortical screw (C)

Fig. 9.15. a An eight-hole 3.5-mm dynamic compression (DC) plate, an eight-hole 4.5-mm DC plate, and a 12-hole 3.5-mm DC plate. Note that the length of the 12-hole 3.5-mm plate is approximately equal to that of the eight-hole 4.5-mm DC plate, whereas the eight-hole 3.5-mm DC plate is much shorter. b A 4.5-mm cortical screw (A), a 3.5-mm cancellous screw (B), and the new 3.5-mm cortical screw (C)

Fig. 9.16a-e. A short 3.5-mm DC plate on the ulna, resulting in failure. a Anteroposterior radiograph of a forearm fracture in a tall 21-year-old man (b). The radius was fixed with an eight-hole 3.5-mm DC plate and an interfragmental compression screw. The ulna was fixed with a six-hole 3.5-mm DC plate, with no fixation in the butterfly fragment. Note the short plate compared with the relatively long ulna, allowing a long lever-arm effect. c Displacement of the fracture at 10 weeks. c Marked limitation of pronation-supination ensued in spite of plaster immobilization. d At that time, further surgery on the ulna allowed anatomical reduction and application of a 12-hole 3.5-mm DC plate. No immobilization was necessary; good forearm rotation returned. e The final result at 18 months

Fig. 9.16a-e. A short 3.5-mm DC plate on the ulna, resulting in failure. a Anteroposterior radiograph of a forearm fracture in a tall 21-year-old man (b). The radius was fixed with an eight-hole 3.5-mm DC plate and an interfragmental compression screw. The ulna was fixed with a six-hole 3.5-mm DC plate, with no fixation in the butterfly fragment. Note the short plate compared with the relatively long ulna, allowing a long lever-arm effect. c Displacement of the fracture at 10 weeks. c Marked limitation of pronation-supination ensued in spite of plaster immobilization. d At that time, further surgery on the ulna allowed anatomical reduction and application of a 12-hole 3.5-mm DC plate. No immobilization was necessary; good forearm rotation returned. e The final result at 18 months a

Fixateur Interne. In osteopenic bone, the improved holding power of the screws in this new form of internal fixation may be helpful, but not at any sacrifice of the more important principle of anatomical reduction. Achieving and maintaining anatomical reduction is more difficult with that technique; therefore, in forearm fractures, the indications are limited (Fig. 9.18).

Site of Plate Application

The ulnar plate is applied to the medial border (Fig. 9.19). Occasionally, removal of bony irregularities from this surface will aid in the placement of the plate.

The radial plate application will depend on the surgeon's choice of incision. Since we favor the anterior approach, the radial plate is applied ideally to the flat surface of the lower third of that bone. Through this same anterior approach the plate may be fixed to the anterior or lateral surface of the middle third and the anterior surface of the upper third. Occasionally, difficulty may be encountered in applying the plate laterally through the anterior incision. If posterior approaches are preferred, especially in the middle third of the radius, the plates are fixed to the lateral or dorsolateral surfaces.

Bone Grafts

Bone grafts are rarely required in the forearm, if concepts of biological fixation are followed. However, if marked comminution is present with some loss of soft tissues or actual bone loss, as in an open fracture, then a cancellous bone graft is indicated.

The bone graft must not be placed along lacerations in the interosseous membrane, as this may favor a cross-union; it should be placed at sites distant from that membrane, to fill all gaps in the bone and to bridge the fracture (Fig. 9.20a). Cancellous grafting is especially indicated if there has been significant bone loss in open fractures. In these instances we prefer internal fixation with a plate to bridge the gap and the use of a cancellous bone graft, usually applied on the fifth to seventh day into a granulating wound, to ensure union (Fig. 9.20b-e).

On rare occasions, however, an external frame may be used. This method may be applied to the forearm, but it is not recommended, except for comminuted fractures of the distal end of the radius and contaminated open fractures with or without sepsis. If external fixation is used as the definitive treatment in diaphyseal fractures, bone grafting should be used to minimize the risk of nonunion.

Wound Closure

Skin closure must be carried out using a meticulous atraumatic technique and with no tension. Suction drainage will reduce hematoma formation and is always used postoperatively, where possible. Not infrequently, in fractures of both bones of the forearm, swelling of the forearm muscles makes closure of one incision without tension difficult. Under these circumstances, we do not hesitate to leave a portion of one wound open, even if it leaves a part of the implant exposed. This has been frequent in our practice; therefore, patients should be informed that they may require a secondary closure of one wound. The ulnar wound, located so close to the subcutaneous a b

Lcdc Platte

Fig. 9.17a-d. The LCDC plate. a The surface of the plate. b The undersur-face of the plate. c Note the oblique undercuts at both ends of each screw hole. This permits a tilting of the screw of 40° maximum in each direction in the long axis of the bone. d Note the trapezoid cross section of the plate and the undercuts between the screw holes. The different undercuts greatly reduce the contact area between the plate and the bone

Fig. 9.17a-d. The LCDC plate. a The surface of the plate. b The undersur-face of the plate. c Note the oblique undercuts at both ends of each screw hole. This permits a tilting of the screw of 40° maximum in each direction in the long axis of the bone. d Note the trapezoid cross section of the plate and the undercuts between the screw holes. The different undercuts greatly reduce the contact area between the plate and the bone a b

Fig. 9.18. a Stable fixation - locking screw create a fixed-angle construct, providing angular stability. b Limited-contact plate design reduces plate-to-bone contact, limiting vascular trauma. c The locking-compression plates have combination locking and compression holes. The locking compression holes allow placement of standard cortex and cancellous bone screws on one side or threaded conical locking screws on the opposite side of each other. A. Threaded hole section for locking screws. B. DCU hole section for standard screws. C. Locking screw in threaded side of plate hole. D. Cortex screw in compression side of plate hole: d Use of locking plate (internal fixator) for a gunshot to forearm (AB) with bone loss, fixed with a locking plate (CD) for better holding power

Fig. 9.18. a Stable fixation - locking screw create a fixed-angle construct, providing angular stability. b Limited-contact plate design reduces plate-to-bone contact, limiting vascular trauma. c The locking-compression plates have combination locking and compression holes. The locking compression holes allow placement of standard cortex and cancellous bone screws on one side or threaded conical locking screws on the opposite side of each other. A. Threaded hole section for locking screws. B. DCU hole section for standard screws. C. Locking screw in threaded side of plate hole. D. Cortex screw in compression side of plate hole: d Use of locking plate (internal fixator) for a gunshot to forearm (AB) with bone loss, fixed with a locking plate (CD) for better holding power

Fig. 9.19. Site of plate application

Fig. 9.19. Site of plate application

Healthy Plate Placement

Fig. 9.20a-e. Bone grafts to forearm. a The graft should be placed on the surface of the bone opposite the interosseous membrane, which is usually torn, to prevent cross-union. b Anteroposterior and c lateral radiographs of a 39-year-old police officer who was struck by a bullet and sustained a fracture of his radius. Initial treatment was debridement, open wound treatment, and fixation with pins and plate. Upon referral at 12 weeks, the pins were removed, and after wound healing, a plate was applied to the anterior surface of the radius. d,e A massive cancellous bone graft allowed sound union of this fracture and a good functional result

e

border, should always be closed. The radial wound, over soft tissues, may be safely left open throughout a portion of its length, since careful placement of the metal implant will bury it under a muscle cover. With early functional rehabilitation, the swelling rapidly disappears from the arm, and it is usually a simple matter to close the wound on the fifth to the seventh postoperative day with sterile tapes or fine sutures. Open treatment of the tense wound prevents necrosis secondary to pressure, prevents sepsis, and has little deleterious cosmetic effect.

Postoperative Care. If, at the end of the procedure, the surgeon feels that anatomical reduction with stable fixation has been accomplished, then early functional rehabilitation should be started. A bulky bandage is applied to the forearm with no plaster cast, and the patient is allowed to move elbow, wrist, and fingers in the immediate postoperative period. In the first 48 h, the arm is elevated on a pillow or a stockinette support and suspended from an intravenous drip pole. The support is removed for elbow and wrist exercises. With stable fixation only soft tissue pain is present, and this quickly disappears from the wound area, making early restoration of function the rule. Even in those instances where one wound cannot be closed, this program should be instituted, since exercise will reduce swelling and allow early secondary closure.

If the surgeon is concerned about the stability of one or both bones because of comminution or poor bone quality, then the bulky postoperative dressing may be removed on the seventh day and replaced with a small functional forearm splint, as described by Sarmiento et al. (1975). This will allow early motion and still afford protection to the internal fixation.

If the fixation is deemed to be stable, the patient should be encouraged to use the arm for all reasonable activities, but should not, prior to evidence of bony union, take part in sporting activities or do any heavy lifting. The patient should be seen at regular intervals, usually monthly, and follow-up radiographs should be taken. With stable internal fixation, the precise time of bone union is difficult to determine. If no untoward radiographic signs of failure are present, such as irritation callus, bone resorption at the fracture site, or loosening of the screws, and if no clinical signs of failure such as inflammation and pain appear, one may assume that healing is proceeding normally. Radiographic evidence of the fracture line disappearing with no evidence of irritation callus is a positive indication of union. The average time for union to occur will be 8-12 weeks, with delays often arising in markedly comminuted fractures requiring bone grafts. Once union has occurred, the patient is encouraged to resume his or her normal life style.

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