Complications of Locked Volar Plates

Rationale and Introduction

Volar plating with locked plates has dramatically reshaped the treatment of distal radius fractures (DRF), as should be evident from the pages of any journal of orthopedics or hand surgery and from the cases posted on this site in the last few years. Indeed, locked volar plating has created the largest shift in DRF treatment paradigms in this author’s clinical lifetime, specifically related to offering patients the option of surgical treatment, as an alternative to casting, for early return to work, lifestyle, and convenience issues. The advances in treatment make it both exciting and challenging to be treating DRF’s at this time.

Along with any new technique come new complications, and locked volar plating is no exception. This article will examine complications that are specific to locked volar plating and seek to explain them on an anatomic basis. The locked volar approach still remains a mainstay of current treatment, as complications should be able to be avoided with careful attention to the details outlined in this article.

Complications of locked volar plating reported in the literature, at national and international presentations, in online discussion forums, in the author’s personal cases, and in cases submitted for review to the author, have included:

(1) irritation/rupture of dorsal tendons due to pastpointing of distal screws
(2) placement of the distal screws into the radiocarpal joint
(3) irritation/rupture of volar tendons due to prominent plates, incomplete reduction, or backing out of distal screws
(4) subsidence of fragments and/or dorsal subluxation of the carpus due to failure to engage the dorsal ulnar fragment
(5) subsidence of fragments and volar subluxation of the carpus due to failure to stabilize the volar rim of the lunate facet
(6) failure to support the subchondral bone by placement of the distal screws too proximally
(7) prominent hardware that is clinically palpable volarly due to implant placement too far radially

Other complications which are much less common include:

(8) inability to remove a plate/screws due to bony adherence to titanium implants

Complications that have been reported but are controversial include:

(9) tendonitis due to titanium; remains a controversial area due to contradictory basic science studies.

The author, in conjunction with Drs. Jorge Orbay and Randi Bindra, has performed 14 cadaveric dissections and examined 39 prepared distal radii. This work served as the basis for the anatomical explanations for these complications. The clinical observations were based on estimated collective case lists of > 600 personal clinical cases, as well as other cases submitted to the author for review.

Analysis of Complications

(1) Tendon Irritation or Rupture or Nerve Injury Due to Pastpointing of Distal Screws

The earliest complication reported and the most common is tendon irritation or outright rupture due to the distal screws extending beyond the dorsal cortex, or pastpointing. The anatomical explanation is easily seen in Figure 1:

Figure 1

The dorsal cortex of the distal radius can be thought of as a dihedral surface, being composed of two planes, one radial and one ulnar to Lister’s tubercle. In the MRI view shown, the two surfaces form a dihedral of approximately 140° (Figure 2a; see also Figure 5), neither of which are parallel to the plane of a lateral xray. Therefore, the lateral xray will not profile either of the dorsal distal radial surfaces. Even if the profile of Lister’s tubercle is ignored, a lateral of the distal radius will not be able to determine if the screw is extending beyond the dorsal cortex (Figure 2b and 2c). In some cases, even intraoperative fluoroscopy may not show the pastpointing, due to the height of Lister's tubercle, the depth of the groove for the EPL, or other ridges of bone (Figure 2c).

Figure 2a

Figure 2b
All screws are past the dorsal cortex and into the tendons,
but none will be seen as too long on a lateral xray.

Figure 2c
Note that three screws are past the dorsal cortex and into the tendons. One screw might show up on the lateral, but the treating surgeon thought, even with fluoroscopic views, that none were too long. Note how the screw tips are hidden, even on fluoroscopic views.

These facts illustrate several concepts. First, the classical AO teaching has included the concept of “bicortical purchase”, that is, surgeons attempted to obtain fixation into the proximal and distal cortices of the bone being plated. A new approach is needed, however, with locked volar plates for the distal radius. The “proximal cortex” that needs to be engaged by the screw with a locked plate is the plate, not the volar cortex. The “distal cortex” in the distal radius is NOT the dorsal cortex, which is actually very thin. This can be appreciated in the MRI in Figure 1 and on a lateral xray (see Figure 3 and Figure 43).

Figure 3

Indeed, the thinness of the dorsal cortex is easily appreciated during surgery when using the dorsal approach. In addition, together with the common finding of a high degree of comminution in DFR’s makes the dorsal cortex an unsuitable point of fixation for the screws. The true source of stability in locked volar plating of the distal radius is support of the subchondral bone. As originally pointed out by McQueen, the subchondral bone is always thick and strong, even in severely osteoporotic patients. If the distal screws are in contact with the subchondral bone, the articular surface will be supported. If the distal screws are placed even a few millimeters proximal to the subchondral bone, subsidence is possible. Therefore, in the context of locked volar plating, the "proximal cortex" is the plate and the “distal cortex” is the subchondral bone.

Surgeons need to think of the distal screws in terms of subchondral support, not in terms of "bicortical fixation." (Surgeons do not have a learning disability, they have an un-learning disablility. Once they learn a concept or technique that has served them well in the past, they have a hard time unlearning it when it no longer applies.)

The second point is that extensor tendons and the posterior interosseous nerve are less than one millimeter away from the dorsal cortex, separated from it by only a thin layer of periosteum (see Figure 1). Pastpointing by only 1 mm will bring the screw into contact with the tendons. The earliest locked volar plates used standard orthopedic screws. Their cutting flutes are on the order of 2-3 mm long (measured along the axis of the screw) and are particularly dangerous. Many of the current generation of locked volar plates use custom distal locking screws, with a taper on the leading end on the order of 1 mm and much smaller cutting flutes. Traditional orthopedic practice has been to have the screw pastpoint beyond the cutting flutes and/or screw tip taper to obtain optimal purchase on the far cortex. This practice, if used in locked volar plating, will bring the screw tip into contact with the extensor tendons or possibly the posterior interosseous nerve (see this case for an illustrious example of nerve impingement). Even screws designed without a formal cutting flute will have a tapering thread, in order to start the thread into the bone. This leading edge of the thread can be problematic if it comes in contact with the tendons, which are forced against the dorsal cortex whenever the patient performs simultaneous wrist flexion and finger extension, or the nerve, which is also in close proximity to the dorsal cortex, lying on the floor of the fourth compartment.

The third point, returning to an analysis of the distal radial anatomy and the lateral xray, is that even oblique views of the distal radius, such as obtained with intraoperative minifluoroscopy, cannot easily define the location of the dorsal cortex, due to the fact that some tendons, particularly the extensor pollicis longus (ELP), lie in a slight indentation in the dorsal cortex (see Figures 4 and 5).

Figure 4

Figure 5

Therefore, even fluoroscopic views may not precisely determine the location of the tip of the screw with respect to the dorsal cortex and the adjacent tendon. Screw tips should stop short of the dorsal cortex by approximately 2 to 4 mm to be sure that they do not pastpoint and come in contact with the extensor tendons or the posterior interosseous nerve.

A fourth point is that there is no need to attempt to place the screws beyond or even close to the dorsal cortex. As observed above, the “distal cortex” is the subchondral bone. An examination of the lateral xray (Figure 3; see also Figures 42 and 43) shows that the subchondral bone stops several millimeters shy of the dorsal cortex. A screw can fully support the subchondral bone and yet stop 2 to 4 mm short of the dorsal cortex. We need an intraoperative guide to screw length.

This led to the development of the concept of the dorsal subchondral support line.

Fig 5A

The purpose of the radius is to position the hand in space. The functional part of the radius in this context is the subchondral plate, supporting the scaphoid and the lunate. The purpose of a subchondral fixed-angle plate is to support the subchondral plate. It does not have to support the entire end of the distal radius: there is a portion of the radius dorsal to the subchondrondral plate that does not support the lunate or scaphoid (dorsal to the red line in photograph below and compare to Fig 5). In fact, the cortex here is paper-thin. The subchondral support pins need to support all of the subchondral plate, but not the thin dorsal cortex. If one were to draw a line (see illustration above) parallel to the long axis of the radius and through the dorsal limit of the subchondral bone, this would define the dorsal subchondral support line. The screw tips need to come to this line but not further dorsally.

Fig 5 Labelled

The dorsal subchondral support line can be determined in the OR by xray. One should not only examine screw length relative to the dorsal subchondral support line on the straight lateral, but also on the semisupinated view (which shows the radial portion of the dorsal cortex and should be aligned with the green line) and the semipronated view (which shows the ulnar portion of the dorsal cortex and should be aligned by the blue line). Note that the subchondral bone on both of these views does not extend to the dorsal cortex.

Clinical Example

A 65 YO woman fell and sustained a DRF. A locked volar plate was placed and intraoperative fluoroscopy (Figure 6) was interpreted as showing proper distal screw placement: just below the subchondral bone, out of the joint, and screw tips just below the dorsal cortex. Plain films (facet PA and facet lateral) were taken (Figure 7a and b) and interpreted as slight ulnar placement of the plate, but good purchase on the dorsal ulnar corner and adequate purchase of the radial styloid, on the PA; and good placement of the distal screws: just below the subchondral bone, out of the joint, and screw tips just below the dorsal cortex, on the facet lateral.

Figure 6

Figure 7a (left) and Figure 7b (right, a lateral facet view)

Followup plain films in the office, probably with a slightly different rotation, indicated that the screw tips were just penetrating the dorsal cortex, but seemed appropriate at the time unpon review by several orthopedic surgeons (see Figure 8).

Figure 8

However, the patient complained about wrist stiffness and pain, more than most patients. There was absolutely no localizing tenderness along the dorsal radius to suggest screw prominence, and there was no irritation with finger range of motion. After several visits without improvment in symptoms or change in the physical exam to suggest screw prominence, a CT scan was obtained (Figure 9).

Figure 9

The CT scan clearly shows that the screws are extending beyond the dorsal cortex. The screws are 2.7 mm in diameter, so they are extending about 3 mm dorsal to the radius. Note the dihedral angle of the two dorsal surfaces, as well as the fact that the screws seem to be lying in a depression such that fluoroscopic views might not reveal their prominence.

The patient was taken to the operating room, where the screws were found to be just a few mm beyond the dorsal cortex. Unfortunately, no photographs were taken by the surgeon.

These three views are of a different but very similar case. Note how much tendon damage was done (Figure 10). The sobering finding, however, is that the damage was done by a screw with only 1 mm of pastpointing (Figure 12) in precisely the wrong place: directly below the EPL tendon (Figure 11). Even minimal pastpointing can be disastrous if positioned in exactly the wrong place.

Figure 10

Figure 11

Figure 12

Each screw in the distal row of the locked volar plate requires unique consideration. The radial styloid screw is at the greated angle, with its axis oriented radially. The length of this screw requires a fluoroscopic view of the dorso-radial surface of the radius, not the dorsal surface, and is always the shortest screw. The screw in the most ulnar position has the greatest requirement for accuracy of placement, due to the nature of the dorsal-ulnar corner fragment. The central screw holes require the most accurate determination of length compared to the dorsal cortex (unless one is attempting rigid internal fixation of the extensor pollicis longus tendon!). Bear in mind these unique characteristics as the fluoroscopic evaluation of the distal row is performed, pronating and supinating the forearm.

Nerve Injury Is Also A Possibility

There is also the possibility of a past-pointing screw hitting the posterior interosseous nerve, causing severe pain. The nerve lies on the ulnar side of the floor of the fourth dorsal compartment, right against the radius. See Figure 1: the posterior interosseous nerve and an artery can be seen just ulnar to the extensor tendons. See also this case.

(2) Placement of the Distal Screws into the Radiocarpal Joint

The distal screws should support the subchondral bone, requiring the placement of the plate as distally as possible, and yet not so far as to place the screws into the joint. Is the plate distal enough, with the subchondral bone optimally supported? Is the plate too distal, with a screw into the joint? This is the intraoperative quandry we face each time we place a locked volar plate. Intraoperative fluoroscopy is routinely used to assess the location of the screws. In conventional fracture management, true PA and lateral xrays have normally been obtained. These views have been adequate prior to the advent of locked volar plating. However, the need for screw placement immediately under the subchondral bone, yet not into the joint, has led to a need for a level of precision not previously required (on the order of a mm or two), and true lateral radiography has been found to frequently be misleading. How can we obtain the accuracy the new technique demands? The anatomy of the distal radius provides the answer.

The Lateral Facet View

Figure 13

Figure 13 is the PA view of a normal distal radius (although there is an ulnar plus variant). The articular surface is curved, but if it is approximated as a straight line, it is tilted approximately 21°. The true lateral of the radius, therefore, does not profile the scaphoid and lunate facets, but views them on at a 21° angle. If the forearm is tilted by approximately 21°, the facets can be seen in true lateral profile, and the view is called the lateral facet view. 

Figure 14 True lateral view

Figure 15 Facet lateral view

Figure 14 is a true lateral, appearing to show penetration of the joint space by several screws, and flagrant violation of the joint space by the radial styloid screw. However, the screw position resolves with a facet lateral view (Figure 15), with the majority of the screws nicely supporting the subchondral bone.

The PA Facet View

The distal articular surface of the radius has an 11 degree volar tilt. A true PA view of the radius, therefore, will give a tangential view of the scaphoid and lunate facets. A true PA of the facets can only be seen with an 11 degree tilt of the radius. This is called the PA facet view.

Many true PA views will seem to show the screw tips extending into the joint. A facet PA (Figure 16) will show that their true location. In practice, both the facet PA and the facet lateral are used.

Figure 14
PA facet view

(3) Irritation or Rupture of Volar Tendons due to Prominent Plates or Backing Out of Distal Screws

Some of the early locked volar plates and some of the first versions of current plates were more prominent than some of the other current generation plates. The Synthes volar 2.4/2.7 distal radius plate, colloquially called the “volar Π plate” , was a great innovation, but had the disadvantages of both raised margins around the screw holes and sharp edges because the width needed to be trimmed to size. When selecting a locked volar plate, be sure that it is properly pre-contoured, low profile, and smooth on its distal margin.

Plate placement can also effect the tendons. If the plate is placed too distally, the flare of the volar rim of the joint will cause the plate to be prominent along its distal margin. The plate should not extend beyond the watershed line (yellow line in Figure 17a), a term coined by Jorge Orbay that refers to the line at the highest (most volar) margin of the radius. This will be the part of the radius (or plate) that is closest to the flexor tendons and therefore at greatest risk of injuring them.

If the plate is placed too radially, a tuberosity called the volar radial tuberosity (see footnote 1), will raise up the radial margin. The tuberosity is easily palpated approximately 2 cm proximal to the volar tuberosity of the scaphoid (which is known to most surgeons in conjunction with the Watson test) and on the most radial aspect of the wrist. A plate placed too radially can become both clinically palpable (“Doc, is this bump supposed to be here? It wasn’t there before the surgery!”) and possibly a problem for the tendons, usually the flexor pollicis longus. If the plate is placed too ulnarly and has a flat profile across its distal margin, a bony feature called the lunate facet buttress (indicated by the red "x" in Figure 17b; see footnote 1) will raise up the ulnar margin. The lunate facet buttress is a bony area just proximal to the lunate facet. The lunate facet projects several millimeters volarly more than the scaphoid facet (Figure 5), and is supported by the lunate facet buttress, which varies in size from a millimeter to several millimeters. Some plates (Hand Innovations, Orthofix, and Acumed; see disclosure at the end of this article) are contoured to fit over the lunate facet buttress and still have the plate flat on the volar surface of the radius. The more distally a plate is placed and the larger the buttress is, the more relevant a contour in the plate becomes.

Figure 17a	Figure 17b
Figure 17a is a volar view of a radius, with the lighting coming from the left to highlight the volar radial tuberosity (indicated by the red “x” in Figure 17a ) and, extending proximally, the volar radial ridge (see footnote 1) (see also Figure 44). The yellow line represents the watershed line. Figure 17b is the same specimen, with the lighting coming from the top to highlight the lunate facet buttress (indicated by the red “x”).

Clinical Example

31 YO male fell off a boat onto a dock and sustained a DRF. He had had a prior DRF at age 15, with some residual deformity. A locked volar plate that is well-contoured to fit a normal distal radius was placed in February of 2006. The volar surface of the radius was flatter than normal due to his prior fall, and since the plate was contoured to fit a normal radius, it did not fit well distally. The pronator quadratus was securely closed over the plate.

Figure 18

Figure 19

Postoperatively, at about 3-4 months, he complained of volar wrist pain with wrist extension and when he was carrying something very heavy. The patient developed paresthesias at 5 months. Surgical exploration was carried out at 7 months due to continuing symptoms.

Figure 20a	Figure 20b

Damage was found to two tendons (Figure 20) but no rupture. There was a hole in the pronator quadratus and the plate was visible and felt to be prominent. The intraoperative assessment by the surgeon was that the properly pre-contoured plate did not fit the abnormal radius and that the screw holes felt “sharp” to his evaluation. The plate was removed and the symptoms resolved. (In addition, I have spoken to the manufacturer and confirmed that this was an early generation design. The design has undergone a number of improvements, such that there is less chance for screw hole “sharpness”. The author is not associated with this company or plate.)

Clinical Example

61 YO female bus driver fell in the schoolyard and sustained a volar Barton’s fracture in April of 2001 (Figures 21 and 22).

Figure 21	Figure 22

A volar Π plate (Pi plate; interestingly, this name was never used by Synthes, but was given to the plate by the community of users, due to the shape of the dorsal plate that was released at the same time and in the same set) was placed to buttress the fracture (Figure 23 and 24).

Figure 23	Figure 24

The fracture was incompletely reduced and the plate’s distal edge was therefore prominent. The patient developed a wrist ache with forceful use beyond 2 hours, which was attributed to her radioscaphoid arthritis. She developed subsidence of the scaphoid into the radius with cystic degeneration within a year (Figure 25), had an ache in her wrist, and retired as a bus driver.

Figure 25

In January of 2007, six years after surgery, she presented with the sudden onset of an inability to flex her thumb IP joint, wrist swelling and wrist tenderness. Xrays showed no progression of the subsidence of the scaphoid into the radius, resolution of the cystic degeneration, and that the plate continued to be prominent volarly.

Figure 26

Figure 27

The diagnosis was made of a flexor pollicis longus rupture due to rubbing on the distal edge of the prominent plate. At surgery, the plate was found to be covered by a dense layer of scar tissue, except at one point. The most radial distal screw (there was one empty hole to the radial side of this screw) was easily seen through a rent in the scar tissue. The cruciate head of the screw was felt to be contributory.

Figure 28

Figure 29

The tendon was grafted with a strip of flexor carpi radialis, as there was no palmaris longus. The bone had overgrowth the plate, but the titanium screws and plate were not firmly bonded to the bone and were removed without problem. She regained excellent range of motion of the thumb.

Figure 30

This is the plate removed from this case (Figure 30). It is a second-generation volar Π plate. The screw holes are surrounded by a raised lip that is high-profile and the distal margin of the plate has a sharply squared-off end. The screws had cruciate heads (see Figure 29). Cruciate heads can form razor-sharp edges if the screw driver slips out of the head while seating the screw. The current generation Synthes locked volar plates are much improved, and all have rounded edges, are lower profile, and use hex or torx screw heads.

There seems to be an advantage to covering the plate with the pronator quadratus (PQ) in order to interpose the muscle between the plate and the flexor tendons. During the initial dissection, most surgeons incise the PQ distally at the edge of the muscle fibers. This line is referred to as the PQ line (see footnote 1). After plate placement, most surgeons repair the PQ muscle. However, the thinness of the fascia of the muscle makes this an exercise in futility, as the sutures typically rip out before the next layer is closed. One technique that has proven to be quite secure is to release the PQ during the original dissection not along the margin of the muscular fibers (the PQ line), but 1-2 mm beyond the PQ line, into the fibrous tissue proximal to the volar capsule. This fibrous tissue, termed the fibrous transition zone (see footnote 1), has been determined in cadaveric dissections not to be part of the mobile volar wrist capsule (comprised of the radioscaphoid, radiocapitate, long radiolunate, and short radiolunate ligaments), but to be immobile and attached to the distal margin of the radius. It is felt that incising the fibrous transition zone should not add unnecessarily to wrist capsular scarring or wrist joint stiffness. Continue the dissection radially 1-2 mm into the fibrous tissue at the base of the first dorsal compartment. If this is done, there will be a 1-2 mm thick, strong margin along the edge of the PQ muscle. This margin will securely hold the sutures and the PQ will remain in place, serving as an interpositional layer between the plate and the flexor tendons.

(4) Subsidence of Fragments and/or Dorsal Subluxation of the Carpus due to Failure to Engage the Dorsal Ulnar Fragment

The dorsal ulnar corner of the radius cannot be neglected, due to the fact that it serves as the attachment point for the dorsal portion of the distal radioulnar joint (DRUJ) ligament. Forearm rotation exerts a very strong force on the dorsal ulnar fragment and can easily displace it. The dorsal ulnar fragment is usually not well visualized on either the PA or the lateral view, and oblique views are needed to assess it. Good screw purchase may be a challenge for such fragments with the volar approach. One should be prepared mentally for this challenge: either get good fixation with the most ulnar screw in the distal row or place a small dorsal, fragment-specific plate.

Clinical Example

A 20 YO male fell from a mountain bike and sustained bilateral wrist injuries. Xrays demonstrated bilateral DRF’s and a right scaphoid fracture. The left wrist is shown in Figures 30 and 31.

Figure 31

Figure 32

The xrays indicated a fracture of the dorsal ulnar corner, so oblique views were obtained to assess its displacment (Figure 33).

Figure 33

The oblique view much better demonstrated the size and displacement of the dorsal ulnar corner. The opposite wrist had a very similar DRF in addition to the scaphoid waist fracture. Open reduction and internal fixation was performed for all three fractures.

Figure 34

Figure 35

Figure 36

A locked volar plate was supplemented with a dorsal .062" K-wire to hold the left radius. Once the radius was fixed, DRUJ stability was assessed and found to be unstable. This was attributed to the ulnar styloid fracture. This was fixed with a .045" K-wire and figure-of-eight wire in a tension band configuration (Figures 34-36).

The patient was seen at one week and xrays obtained (Figures 37-39).

Figure 37

Figure 38

Figure 39

The follow-up views demonstrated displacement of the dorsal ulnar corner, in a manner identical to the original injury (Figures 36-38). A critical review of the immediate post-op films shows that the dorsal ulnar corner was not fixed with the volar plate and that the K-wire fixation was not stiff enough alone to resist the deforming forces. One could also speculate that the instability of the DRUJ was entirely or in part due to the dorsal ulnar corner rather than the ulnar styloid fracture. It was felt that the instability had a chance of progressive subsidence, and further fixation was required. (The opposite wrist had an identical subsidence and was also re-operated.)

Figure 40	Figure 41	Figure 42

The patient was returned to the operating room where a dorsal plate was placed through a dorsal incision (Figures 40-42). This reduction was maintained and at one year the patient had good motion with little to no pain.

(5) Subsidence of Fragments and Volar Subluxation of the Carpus due to Failure to Stabilize the Volar Rim of the Lunate Facet

Small volar rim fragments are difficult to stabilize and experience has shown that they are easily underestimated. Common mistakes are to place the plate too radially, too proximally, or to choose a technique or plate that cannot stabilize the volar rim of the lunate.

Figure 43	Figure 44

Figure 45

Figure 42 is the lateral view of a dried radius from the ulnar side, and Figure 43 is an xray of that specimen in approximately the same projection (the scaphoid and lunate facets are overlapping in the dried radius but offset in the xray). Figure 44 identifies several anatomic features. The key point is that the lunate facet projects quite a bit volarly (see also Figure 2), and that the center of the facet is directly over the volar aspect of the radius. It is not over the center of the medullary canal. The load from the carpus places a force on the lunate facet that has a component that is distinctly volarly-directed. This, combined with the extent of volar projection of the lunate facet, makes lunate rim fractures very unstable.

No locked volar plate extends to the volar lip of the lunate facet. The one that comes the closest is the Synthes 2.4 LCP Volar Juxta-Articular Distal Radius Plate. Most designs do not want to extend that far past the watershed line and risk injuring the flexor tendons, and how far a plate should extend distally is controversial. However, in the case of a fracture of the volar lip of the lunate facet, some kind of stabilization is required, and some violation of the watershed line is needed. Various techniques have been used or proposed, including using the Synthes Juxta-Articular plate, placing a standard plate more distally, using a fragment-specific approach, or K-wires. The effectiveness of each approach depends on the fragment size, the technique used, and the actual shape of the implant. The Synthes Juxta-Articular plate or the fragment specific approaches are probably the most common, but each have their limitations. The Synthes plate unnecessarily extends beyond the watershed line for the scaphoid facet, which does not need support. The fragment specific approach is less stable and more complex to apply.

Clinical Example

A19 YO male fell sustaining a DRF. Xrays showed a very distal volar lip fracture of the radius and slightly rotated radial styloid fracture, with just enough volar subluxation of the lunate to suggest volar instability (Figures 46 and 47).

Figure 46	Figure 47

A CT scan (Figure 48) and CT reconstruction with the carpus removed (Figure 49) confirmed the size, shape, and location of the fragments, as well as the volar subluxation of the lunate.

Figure 48	Figure 49

It was felt that a standard locked plate would not stabilize this fracture, and a fragment-specific technique was used (Figures 50 and 51).

Figure 50	Figure 51

Another clinical case, with a more complex fracture, was stabilized with a similar technique.

Figure 52	Figure 53

(6) Placement of the Distal Screws too Proximally and Failing to Support the Subchondral Bone

Older patients with severe osteoporosis are a challenge to treat. Locked volar plates take advantage of the two strongest areas of bone, which are the volar cortex just proximal to the metaphyseal bone and the subchondral bone. Figure 43 is an xray of an osteoporotic bone in the author’s collection. The bone is quite fragile. However, the xray clearly demonstrates that these two areas are the most dense, with little bone showing in the dorsal cortex of the metaphyseal bone or a few mm proximal to the subchondral bone. While distal screws can support the joint several mm away from the subhcondral bone in younger patients, they need to be placed distally in the osteoporotic patient. If the screws are several millimeters away from the subchondral bone, they may settle thorough the cancellous metaphyseal bone until they reach the subchondral bone. The author is not aware of any case in which the distal screws have settled through the subchondral bone.

(7) Prominent Hardware that is Clinically Palpable Volarly due to Implant Placement too far Radially

Palpate the volar radial tuberosity (Figure 44) in your own wrist. It is 2 cm proximal to the volar tuberosity of the scaphoid (the part of the scaphoid where you push for the Watson test), at the most radial border of the wrist. It is quite subcutaneous, with little overlying fat. Plates that are placed too radially can be easily palpated by the patient. Care must be taken, prior to the drilling for the first screw, to assess the plate placement. Most plate systems have methods to hold the plate in place while the placement is assessed radiographically, either K-wire holes or drill guides that accept K-wires. Once the position of the plate is tentatively determined, remove the retractors, replace the skin edges, and palpate the skin over the volar radial tuberosity. Move the plate if required.

(8) Inability to Remove a Plate/Screws due to Bony Adherence to Titanium Implants

There have been reports of titanium screws being so firmly bonded to the bone that the heads shear off, the driver tip shears off, or the head strips out. The surgeons have had to resort to breaking the implants and burring off any projecting screw remnants. This point remains controversial. Some authors recommend the use of stainless steel implants to avoid bonding and screw breakage, and others claim that there is no chemical bonding between bone and titanium. It is interesting to observe the competing claims of two groups with very different agendas: the trauma companies deny that bonding to their titanium implants exists, while at the same time the total joint companies tout the strength of the bonding to their titanium implants. Many surface treatments, from polishing to chemical treatment or hydroxyapetite coating, have been tried to avoid or enchance bonding. The controversy does not seem to have a resolution at this time, and there does not seem to be a clear reason to avoid titanium locked volar plates. In the one case of late titanium plate removal in the author’s experience, at six years after implantation (case cited above, involving a second-generation Synthes titanium plate, Figures 28-30), all screws were easily removed, once the bony overgrowth covering the screw heads was removed.

(9) Tendonitis due to Titanium

Tendonitis due to titanium is even more controversial than the inability to remove titanium screws due to bonding. Some authors of animal studies report finding titantium synovitis that is more than found with stainless steel, while others report the opposite. The influence of synovial fluid on the formation of tendonitis is also controversial. My personal experience, with volar titanium plates in for from one to six years, is that I have not seen synovitis. At this time, there does not seem to be a clear reason to avoid titanium locked volar plates.

End Notes

Here are some suggestions to avoid complication and to improve your results:

(1) Nothing is so humbling as reviewing your own cases two or so years later. Be brutal in your criticisms.
(2) Perform a cadaveric dissection. When you know you don’t have to repair anything and the exposure can be exceedingly wide, a lot of new lessons will be learned. Our normal exposure windows hide as much as they reveal.
(3) Obtain and study a distal radius. You can’t reconstruct a bone if all you look at are shadows (xrays) and microviews (surgical exposures). I have kept one on my desk for 14 years (seen in Figures 4, 5, and 42), and this one bone has taught me a treasure-trove of lessons.

Footnote 1 These terms have been proposed by David Nelson, Jorge Orbay, and Randi Bindra, in an article in submission to the Journal of Hand Surgery, American. See this article on eRadius.

Disclosure: the author has designed a locked volar plate and receives royalties related to that plate.

The author would like to acknowledge the contribution of Drs. Jorge Orbay and Randi Bindra for the development of the new anatomic terms, and Drs. Kendrick Lee, Stefan Zachary, Michael Grafe, and Rob Medoff for the contribution of clinical material. The author is actively solicting the submission of complications, so that they can be collated, analyzed, and disseminated to the surgical community. Contact the author at