CHAPTER SYNOPSIS:
The intricate anatomy and complex kinematics of the carpus can be disrupted by traumatic, degenerative, inflammatory, neoplastic, or congenital conditions. When only selective joints within the carpus are involved, reconstructive efforts are undertaken to eliminate pain and preserve motion through selective carpal bone deletion or limited intercarpal fusions. When destruction occurs within both the radiocarpal and midcarpal joints (“pancarpal”) these limited reconstructive efforts are inappropriate. Failing conservative management, patient and surgeon must carefully choose between total wrist arthrodesis versus total wrist arthroplasty.
IMPORTANT POINTS:
Total wrist arthrodesis aims to eliminate pain at the expense of motion while providing a stable platform for power grip.
Total wrist arthroplasty achieves range of motion similar to limited intercarpal fusions and improves function during low demand activities.
The vast majority of activities of daily living (ADLs) can be accomplished with limited wrist motion.
Perineal care and manipulating the hand in confined spaces are the most commonly reported limitations following total wrist arthrodesis.
Strict lifetime limitations imposed following total wrist arthroplasty :
Avoid impact loading of the wrist (tennis)
No repetitive forceful use of the hand
Only intermittent lifting greater than 10 pounds
TOTAL WRIST ARTHRODESIS INDICATIONS/CONTRAINDICATIONS:
Indications:
Active individual with pancarpal arthritis
Failed implant arthroplasty
Progressive degeneration following limited intercarpal fusion
Severe spastic contracture
Bone loss secondary to ballistic injury or tumor resection of the carpus/distal radius
Contraindications:
Active wrist infection
Open distal radial physis
Insufficient soft tissue envelope
Patient with tetraplegia with adaptive function
Bilateral (relative)
Patient with rheumatoid arthritis with multiple upper limb joint involvement (relative)
TOTAL WRIST ARTHROPLASTY INDICATIONS/CONTRAINDICATIONS:
Indications:
Low demand patient with pancarpal arthritis
Patient with rheumatoid arthritis with multiple joint involvement
Bilateral pancarpal arthritis (relative)
Contraindications:
Active wrist infection
High functional/demand patient
Highly active rheumatoid disease (hyperlaxity and severe bone loss)
Radial nerve palsy
Required upper limb use for transfers or ambulatory aids
Previous wrist arthrodesis or proximal row carpectomy (relative)
CLINICAL/SURGICAL PEARLS AND PITFALLS:
General
Evaluate for concomitant median nerve compression at the wrist
Critical evaluation of the distal radioulnar joint (DRUJ)
Treat lower-extremity joints first
Treat wrist prior to metacarpophalangeal (MCP) joints
Optimize nutritional status for improved wound healing
Longitudinal incision/preserve sensory nerves
TOTAL WRIST ARTHRODESIS
Use plate fixation whenever possible
Preoperative splinting/casting to simulate arthrodesis
Release and transpose extensor pollicis longus (EPL)
Central fusion column:
Capitolunate joint
Radioscaphoid joint
Radiolunate joint
Third carpometacarpal (CMC) joint (controversial)
Include scaphotrapeziotrapezoid (STT) joint or second CMC joint if symptomatic
Bone graft (distal radius, resected distal ulna, iliac crest, or allograft)
Fuse wrist in 10 to 15 degrees of extension, slight ulnar deviation (improves power grip)
Meticulous wound closure over a suction drain
Soft/bulky dressing ± volar splint
TOTAL WRIST ARTHROPLASTY
Honest patient education regarding lifetime restrictions and potential implant failures necessitating complex salvage procedures
Preoperative templating to predict implant size and alignment
Surgeon education and cadaveric practice with implant of choice
Strict adherence to specific implant technique and intraoperative imaging for precise component positioning
HISTORY/INTRODUCTION/SCOPE OF THE PROBLEM
Total wrist arthrodesis and total wrist arthroplasty share the common goal of relieving pain in the wrist ravaged by degenerative, posttraumatic, inflammatory, neoplastic, or congenital conditions. The obvious distinction between these reconstructive efforts is the elimination versus preservation of motion. Multiple studies have evaluated the functional outcomes following wrist arthrodesis. Current fusion techniques report fusion rates exceeding 98% with predictable functional results. The most frequently reported limitations following arthrodesis involve perineal care, screwdriver use, button fastening, hair combing, and jar opening. These limitations become more pronounced in the patient undergoing bilateral wrist arthrodeses or in those suffering with ipsilateral shoulder and elbow arthropathy. Swanson developed the first wrist implant as an alternative to wrist arthrodesis aiming to maintain sufficient wrist motion to perform all daily activities without limitation. Numerous investigators have attempted to quantify the wrist range of motion used during activities of daily living (ADLs; Table 9-1 ). Although the numbers vary, all studies conclude that preserving some wrist motion is preferable and enhances one’s performance of ADLs. None of these studies on wrist motion report a requirement of either wrist flexion or extension greater than 35 degrees. Proponents of wrist arthroplasty claim that preservation of motion is not only preferred but also enhances function. Current arthroplasty designs achieve a final arc of wrist motion similar to several commonly performed procedures (proximal row carpectomy, radiolunate fusion, four-corner arthrodesis). Therefore, wrist arthroplasty appears to provide the requisite range of motion to accomplish ADLs. Patients with rheumatoid arthritis and wrist fusion on one side and arthroplasty on the other prefer arthroplasty. Preserving motion in the painful/deformed wrist may improve upper limb function during vocational and avocational activities but should never take precedence over achieving predictable pain relief and stability.
| Fusion Rates: |
| AO/ASIF plate: 98.5% |
| Non-AO plating techniques: 73.5% |
| Time to Fusion: 10.3 Weeks |
| Pain Relief |
| Wrist fusion: 85% |
| Motion-sparing procedures: 66% |
| Activities of Daily Living |
| 85% of tasks completed normally |
| 92% of tasks completed in normal manner |
| 92% of tasks completed in normal time |
| Return to Work |
| 65% returned to same job (typically heavy labor) |
| 25% returned to less strenuous work |
| 10% did not return for reasons unrelated to wrist |
Evaluation of the painful/deformed wrist begins with a thorough history and physical examination, aiming to establish which reconstructive procedure best suits the needs and desires of each individual patient. Specifically, one looks for evidence of inflammatory, neoplastic, infectious, or congenital conditions. Establishing the patient’s functional goals and anticipated physical demands is critical in determining the correct treatment protocol. Radiographic evaluation is used in conjunction with physical examination of the wrist to fully delineate which of the many carpal articulations are damaged secondary to the underlying pathology. Meticulous palpation of each individual carpal articulation is the most powerful tool one has in arriving at the correct conclusions. Degenerative changes limited to one or two carpal articulations may be amenable to selective carpal bone deletion or limited intercarpal arthrodesis with potential preservation of motion. When destruction occurs within both the radiocarpal and midcarpal joints (“pancarpal”) these limited reconstructive efforts are inappropriate ( Fig. 9-1 ). Failing conservative management, patient and surgeon must carefully choose between total wrist arthrodesis or total wrist arthroplasty.
The history of achieving solid wrist fusion dates back a century. Ely in 1910 reported fusing the wrist of a patient afflicted with tuberculosis. The base of the third metacarpal was fused to the distal radius using an anterior tibial graft sutured in place. Since this original report, several innovative techniques have been described, all reflecting the technology and techniques of their times. The earliest investigators used several different autogenous bone grafts that were skillfully contoured and fitted into the prepared carpal bed to promote radiocarpal fusion. The most well known of these grafts are the radial turnabout graft (Gill 1923), iliac crest graft (Abbott 1942), and split rib grafts (Colonna 1944). The introduction of metallic implants revolutionized wrist arthrodesis. The Nalebuff technique describes placing smooth intramedullary rods down the metacarpal shafts, through the carpus and into the radius. Several modifications to this technique have been reported, including inserting the rods in the intervals between the metacarpal rays and changing the configuration of the rods. Although controlling wrist position can be challenging, these techniques remain viable options in achieving wrist arthrodesis in the patient with rheumatoid arthritis with severe osteopenia. Other options described to promote solid fusion include compression staples or tension band wiring. Louis and colleagues first reported on performing proximal row carpectomy and subsequent radiocapitate fusion. External fixation plays a role in achieving arthrodesis in the skeletally immature, the infected wrist, wrists with severe loss of bone stock, and others where traditional implants are not appropriate. We have used external fixation as an intermediate step in some of these populations to prepare the fusion. Larsson reported on 23 wrist arthrodeses performed with dorsal compression plating from the distal radius across the carpus and onto the second metacarpal. Dorsal compression plating has several advantages including enhanced fusion rates, shorter duration of immobilization, no violation of the metacarpophalangeal (MCP) joints, and well-tolerated implants. Our technique for wrist fusion using dorsal compression plating is described in detail later in this chapter.
Swanson introduced the first wrist implant with wide application in the United States. This silicone implant functions as a flexible spacer with positive early results reported for pain relief and range of motion. Unfortunately, long-term followup revealed high rates of subsidence, implant breakage (52% at 3 years), and silicone synovitis. The evolution of articulated implants that followed has been one of trial and error. First-generation designs were plagued by wrist imbalance, instability, and loosening accompanied by severe bony erosion and cortical penetration. Current total wrist arthroplasty designs share several features, all intended to diminish instability/imbalance and improve fixation. Adams and colleagues have outlined specific criteria aimed at optimizing long-term outcomes. Distal component fixation should be primarily within the carpus and should be accompanied by a solid intercarpal fusion. Avoiding fixation into the metacarpals is intended to diminish the risk of bony erosion and potential cortical penetration. The intercarpal fusion provides a broad support for the distal component. Screw augmentation has been shown to have favorable biomechanical characteristics. Press fit designs relying on osteointegration over cement fixation potentially enhances long-term durability while diminishing bone loss should revision become necessary. The radial component should be designed to minimize the need for significant bone resection, thus preserving the joint capsule for later repair and enhanced stability. A broad, ellipsoid, semi-constrained articulation has biomechanical characteristics favoring stability. Last, the option for retention of the distal ulnar with preservation of the distal radioulnar joint (DRUJ) should be incorporated in the implant design.
INDICATIONS/CONTRAINDICATIONS
Determining the most appropriate treatment option for patients afflicted with pancarpal degeneration can be challenging. No one criterion can be used to completely guide management toward arthrodesis or arthroplasty. Instead, the objective physical and radiographic findings must be integrated with the patient’s unique occupational and recreational demands with the goal of arriving at a comprehensive and individualized treatment algorithm. Besides active wrist infection and skeletal immaturity, there are few absolute contraindications to either wrist arthrodesis or arthroplasty. However, certain characteristics favor one option over the other.
Activity Level
The single most important determinant in our opinion between wrist fusion or arthroplasty is the intended physical demands placed on the reconstructed wrist. Young, active patients and those anticipating continued participation in physically demanding pursuits should undergo wrist arthrodesis. Current prosthetic designs cannot withstand the high stresses of an active lifestyle with unacceptable risk for wrist instability and implant failure. Included in this unique patient population are those dependent on upper limb support during ambulation or transfers. However, intermittent use of a cane for support is acceptable as long as a supportive wrist splint is used during these activities.
Multiple Joint Involvement
The impact of wrist arthrodesis when paired with concomitant shoulder and elbow derangement is difficult to quantify. Without a doubt, the adverse impact of lost motion at the wrist is greater in patients afflicted with arthritis involving the other joints of the upper limb. The most significantly limited tasks involve personal hygiene. Thus, the decision to proceed with arthrodesis must be individualized, and many hand surgeons believe that concomitant shoulder and elbow arthritis is a relative contraindication to proceeding with wrist fusion. Modeling or “test driving” a fusion by placement of a rigid wrist splint preoperatively affords the patient an opportunity to evaluate how the ultimate loss of motion will affect their activity level and comfort. Individualized counseling and honest discussions of the risks and benefits to both wrist fusion and arthroplasty are required prior to proceeding with the definitive procedure.
The debate on whether to reconstruct the hands or wrists prior to the shoulders or elbows is currently unresolved. Traditional teaching has stated that proximal reconstructions should be the initial focus. However, there is little doubt that a painful/deformed wrist and hand will adversely affect the rehabilitation of more proximal reconstructions. These authors prefer a personalized approach to this issue rather than being overly dogmatic. Counseling of the patient and eliciting direct input from the therapist assists in designing the overall treatment algorithm.
Bilateral Wrist Disease
Managing the patient with bilateral pancarpal arthritis can be challenging. Careful evaluation of anticipated activity level, use of ambulatory aids, concomitant shoulder and elbow derangement, and the impact of lost motion are even more critical in this population. As previously stated, patients with arthrodesis on one side and arthroplasty on the other prefer the arthroplasty. It has been suggested that even young patients with bilateral disease benefit from arthrodesis on one side and arthroplasty on the other. In contrast, Rayan and colleagues performed a functional assessment of bilateral wrist arthrodeses and concluded that patients maintained an appropriate level of function to perform most ADLs, including personal hygiene. The ideal position of fusion for each wrist in patient’s undergoing bilateral arthrodesis remains debated. Some studies suggest enhanced functional outcomes in patients who underwent arthrodesis of one wrist in the standard position (10 to 15 degrees of extension) with the contralateral wrist fused in slight flexion. Others recommend both arthrodeses be placed in the standard position defined earlier. Clearly, the patient with bilateral pancarpal arthritis requires significant counseling regarding the risks and benefits of fusion versus arthroplasty. As stated earlier, it has been useful to the senior author to splint or cast patients temporarily to simulate wrist fusion and “test drive” its impact on daily function and living.
Extensor Tendon Dysfunction
Lack of wrist extension secondary to rupture of the extensor carpi radialis longus and brevis tendons or radial nerve palsy is an absolute contraindication to performing total wrist arthroplasty. In contrast, arthrodesis predictably achieves a stable and well-aligned wrist, both prerequisites for effective upper limb function. This does not imply that total wrist fusion should be the primary reconstructive option secondary to radial nerve palsy. Excellent results can be achieved with alternative procedures including nerve repair/transfer/ reconstruction or tendon transfers to restore function. Equally important are the adaptations patients with tetraplegia use to optimize their upper limb function. Eliminating wrist motion can have deleterious effects on this unique patient population and must be critically evaluated.
The status of the extrinsic digital extensors remains a controversial topic. These authors believe that the need for simultaneous extensor tendon reconstruction is not a contraindication for wrist arthrodesis.
Inflammatory Arthropathy
Patients with inflammatory arthropathy, most commonly rheumatoid arthritis, require special attention. This population often suffers with bilateral wrist disease along with multiple joint involvement. Preserving some wrist motion often makes tasks of daily living easier. Therefore, the lower demand patient with rheumatoid arthritis is often an excellent candidate for total wrist arthroplasty. However, patients inflicted with severe disease characterized by highly active synovitis, bony erosion, and carpal instability are poor candidates for arthroplasty. The lack of bony support and instability lead to unacceptably high rates of implant loosening and failure. Therefore, patients must be screened for highly active disease, and in these patients arthrodesis provides a more functional and durable outcome.
Bone Deficiency
Severe bone loss can arise from trauma, tumor, or metabolic or inflammatory disease. The remaining bone stock cannot support the implants used in wrist arthroplasty. Wrist arthrodesis is the procedure of choice in patients with severe bone loss and often requires the use of either corticocancellous iliac crest autograft, bulk allograft, or vascularized bone transfer. Included in this group are patients with failed total wrist arthroplasty and its associated bone loss. These patients present difficult challenges in achieving a solid, well-aligned, and stable arthrodesis.
Spastic Contracture
Spastic contracture is an absolute contraindication to wrist arthroplasty. Wrist fusion predictably places the hand in a more neutral position, improving hygiene, function, and cosmesis. Concomitant proximal row carpectomy is often performed to facilitate positioning the wrist in neutral or slight extension. Hargreaves and colleagues evaluated the functional outcomes of wrist fusion in this population. Ten patients with 11 wrist fusions were evaluated. Preoperative function defined as “none” or “assist” was improved to “assist” or “simple.” Solid fusion was achieved in all patients, 9 with plate osteosynthesis and 2 with crossed K-wires. Arthrodesis is contraindicated in patients who use wrist flexion for release function because fusion would eliminate this important adaptation.
SURGICAL TECHNIQUE
Preoperative Evaluation
In addition to general historical, physical, and radiographic assessment, special emphasis should be placed on the neurovascular, musculoskeletal, and integumentary systems. Critical attention to these specific areas will help avoid specific pitfalls commonly shared between wrist arthrodesis and arthroplasty.
The preoperative status of the median nerve must be critically analyzed. Median neuropathy occurs in up to 14% of patients undergoing wrist arthrodesis. Often these cases could be prevented by appreciating subtle subjective and objective finding during the preoperative evaluation. Electromyographic studies are recommended in any patient manifesting even minor complaints related to their median nerve prior to undergoing wrist fusion or replacement. We maintain a low threshold for simultaneous carpal tunnel release to avoid nerve embarrassment arising from postoperative swelling.
Preoperative assessment of shoulder and elbow function is important in the decision-making process. Patients with loss of motion at other joints may be more reluctant to sacrifice wrist motion and are often more appropriate candidates for wrist arthroplasty. Careful documentation of digital motor function and potential tendon ruptures allows for appropriate counseling and operative planning should tendon repair or transfer be required. Equally important is the preoperative documentation of active wrist extension power and functional digits, both prerequisites for performing wrist arthroplasty.
The DRUJ requires special mention. A thorough evaluation both physically and radiographically of the DRUJ must be performed prior to fusion or replacement. Pronation and supination of the wrist are quantified, as is the ulnocarpal relationship. Patients demonstrating arthritic changes of the DRUJ or ulnocarpal abutment require a surgical remedy. However, intraoperative scrutiny of the DRUJ is the ultimate determinant of whether the DRUJ is maintained or ablated. In similar fashion, the second and third carpometacarpal joints are evaluated. In the face of advanced degenerative changes or significant carpal bossing, these joints should be fused.
High-quality radiographs in the posteroanterior (PA) and lateral planes allow for preoperative templating prior to wrist arthroplasty. Implant size and the anticipated positioning of the components are estimated.
Careful handing of the soft tissues is always exercised and even more critical in the population undergoing wrist arthroplasty or arthrodesis. Previous incisions should be identified and incorporated during surgical exposure when appropriate. Many of these patients suffer with inflammatory/autoimmune diseases and are at increased risk for wound healing complications. The patient’s rheumatologist or primary medical physician should be consulted with regard to optimizing nutritional status and outlining proper management of their immune modulating drugs and all other medications.
Total Wrist Arthrodesis Surgical Technique
Numerous well-described methods for achieving solid wrist arthrodesis are available. The techniques have evolved over the last century from transposition bone grafting to intramedullary pinning to plate and screw fixation. Today the majority of hand surgeons favor arthrodesis with plate and screw fixation. The advantages of this technique are solid fixation under compression, potentially diminished time to fusion, shorter duration of immobilization, ease of positioning, avoidance of MCP joint violation, well-tolerated implants, and the application of local cancellous bone graft. However, the approach to wrist arthrodesis should not be unidimensional. Intramedullary fixation remains a viable option in the patient with extremely poor bone stock or a compromised soft tissue envelope. When the bone stock is even remotely adequate, regardless of the derangement of carpal anatomy, the senior author prefers to perform wrist arthrodesis with plate and screw fixation. A detailed description follows of our previously published technique for wrist arthrodesis using precontoured wrist fusion plates.
Incision
A longitudinal or gently curvilinear incision is made just distal to the midshaft of the third metacarpal and extending proximally over Lister’s tubercle to the radius metaphysis–diaphysis junction ( Fig. 9-2 ). Crossing veins are ligated, but care is taken to leave longitudinal veins and their accompanying cutaneous branches from the radial and ulnar sensory nerves. Suprafascial dissection in the areolar plane exposes the extensor retinaculum and dorsal forearm fascia.
