DEFINITION

Arthritis between the radial styloid and the distal aspect of the scaphoid can lead to pain, weakness of grip, and limitation of motion. This arthritis can occur in the early stages of a variety of pathologic states of the radiocarpal joint.

Radial styloidectomy is a technique that involves resection of the distalmost aspect of the articular surface of the distal radius.

A radial styloidectomy can be performed as a distinct procedure via an open incision or by arthroscopic means. It is more commonly undertaken as an adjunct procedure with reconstructive or salvage procedures for scaphoid nonunions, carpal instabilities, Kienböck disease, or posttraumatic arthritis of the

radiocarpal joint.10,22

 

 

ANATOMY

 

The radial styloid is the distalmost projection on the lateral aspect of the terminal end of the radius (FIG 1A,B).

 

 

When viewed from the lateral aspect, the styloid has a gentle slope volarly, placing it below the midcoronal longitudinal axis of the radius.

 

The intra-articular component of the radial styloid encompasses part of the scaphoid facet.

 

The extra-articular aspect of the styloid serves as the origin of several dorsal, palmar, and radial extrinsic ligaments that are vital to normal carpal kinematics (FIG 1C).

 

 

 

FIG 1 • A,B. The radial styloid outlined on a standard posteroanterior (PA) and lateral wrist radiograph. C. Palmar and dorsal extrinsic ligaments of the radiocarpal joint. Note the broad origin of the dorsoradial ligament. The RCL originates from the tip of the styloid. The RSC and LRL ligaments are separated by a well-defined sulcus readily seen arthroscopically.

 

 

The palmar radiocarpal ligaments serve as a constraint to radiocarpal pronation, ulnar translation, and distal pole scaphoid stabilization. Global disruption of this complex has been implicated in perilunate dislocation. The palmar radiocarpal ligaments are composed of the following structures:

 

 

The radial collateral ligament (RCL) is a thin structure that originates from the tip of the radial styloid and inserts into the waist and distal aspect of the scaphoid. The integrity of the ligament is always sacrificed

with a radial styloidectomy, but no untoward effects have been reported.3,4

 

The radioscaphocapitate (RSC) ligament originates from the palmar cortex of the distal radius coursing distally and ulnarly, attaching to the waist and proximal cortex of the distal pole of the scaphoid and the body of the capitate.3,4

 

The long radiolunate (LRL) ligament originates from the palmar cortical margin of the distal radius immediately adjacent and medial to the RSC ligament. It is separated from the RSC by a distinct sulcus that serves an arthroscopic landmark.3,4

 

The dorsal radiocarpal (DRC) ligament originates broadly from the dorsal rim of the distal radius around the tubercle of Lister, coursing ulnarly, distally, and obliquely to insert on the dorsal tubercle of the triquetrum.

 

 

The radialmost fibers of this ligament also insert on the dorsal lunate.

 

 

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FIG 2 • Styloidectomies as described by Nakamura12 and Siegel and Gelberman.16

 

 

The DRC ligament, in concert with the dorsal intercarpal ligament, has a crucial role in maintaining normal carpal kinematics and carpal stability and preventing ulnar translation of the carpus.19,20

 

Siegel and Gelberman16 examined the effect of three different styloidectomy configurations on palmar radiocarpal ligament integrity in a cadaver model (FIG 2).

 

 

The most conservative osteotomy (short oblique) removed only 9% of the RSC and none of the LRL ligaments.

 

A vertical oblique osteotomy sacrificed 92% of the RSC and 21% of the LRL ligaments.

 

A transverse styloidectomy was the most aggressive and resulted in loss of 95% of the RSC and 42% loss of the LRL ligaments.

 

 

Nakamura et al12 examined the effect of radial styloidectomy on carpal alignment and ulnar translation in cadaveric limbs. They demonstrated that as a larger segment of the radial styloid was resected (see FIG 2), a greater tendency toward ulnar translation, as manifested by decreased stiffness, was observed. No frank ulnar translation with axial loading was observed.

 

 

Based on their analysis, they recommended that no more than 3 to 4 mm of radial styloid should be resected. This correlated with a short oblique styloidectomy as described by Siegel and Gelberman.16

 

Although ulnar translation is a stated complication of overly vigorous styloidectomy, Viegas et al19 demonstrated in a cadaver model that ulnar translation can occur only with resection of the DRC, RSC, LRL, and short radiolunate (SRL) ligaments.

 

 

 

FIG 3 • Stages of arthritis with SLAC. SLAC I: degenerative changes are confined to the radial styloid. SLAC II: joint space narrowing of the entire radioscaphoid articulation. SLAC III: chondral changes in the radioscaphoid and capitolunate joint.

 

PATHOGENESIS AND NATURAL HISTORY

Scapholunate Instability

 

Watson and Ballet21 reviewed radiographs of individuals with scapholunate dissociation to establish the sequential progression of arthritis in the scapholunate advanced collapse (SLAC) wrist (FIG 3).

 

 

SLAC I: Degenerative changes are confined to the radial styloid area.

 

 

SLAC II: Changes are characterized by joint space narrowing involving the entire radioscaphoid articulation. SLAC III: Changes involve additional arthritis between the capitate and lunate.

 

Several authors have examined the mechanics of scapholunate dissociation in cadaver models and have demonstrated that scapholunate instability leads to a shift in the contact pressures from the proximal pole of scaphoid articulation with the radial articular surface toward the distal pole of the scaphoid with the dorsal lip

of the radial styloid.7,8 The pathomechanics of these changes can occur even before the frank radiographic appearance of scapholunate diastasis is present (ie, static scapholunate instability). Prolonged exposure to these abnormal contact stresses leads to the predictable arthritic changes described earlier.

 

 

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Scaphoid nonunion

 

 

With an unstable scaphoid fracture, the proximal pole of the scaphoid remains firmly fixed to and extends with the lunate through an intact scapholunate interosseous ligament. The distal pole adopts a flexed posture, which can then impinge on the radial styloid, leading to abnormal contact stresses and arthritic changes.

 

The natural history of scaphoid nonunion has not been established by rigorous prospective analysis. Nonetheless, most surgeons believe that unstable scaphoid fractures result in abnormal carpal kinematics with a dorsal intercalated segment instability (DISI) deformity and subsequent arthritis (scaphoid nonunion advanced collapse [SNAC] wrist).

 

Vender et al18 examined the radiographs of 64 patients with symptomatic scaphoid nonunions and showed a high frequency of degenerative changes that occurred in a predictable sequence similar to the findings of SLAC wrist. Initial degenerative changes were seen between the radial styloid and the distal fragment of the scaphoid nonunion. Changes then progressed to include the midcarpal joint with sparing of the proximal

pole scaphoid and radiolunate articulation.18 Inoue and Sakuma9 reviewed 102 patients with scaphoid nonunions clinically and radiographically; they found that arthritis initially developed at the scaphoid-radial styloid articulation and subsequently the midcarpal joint. All patients had radiographic arthritis within 10 years of injury. They also demonstrated that although radiographic progression did not correlate with wrist pain, it did correlate with a decrease in grip strength and range of motion.

 

Impingement after triscaphe (scaphoid-trapezoid-trapezium) fusion

 

 

Rogers and Watson14 reviewed 93 patients after triscaphe fusion and found a 33% incidence of painful impingement between the fusion mass and the radial styloid that resolved after limited radial styloidectomy. They hypothesized that the fixed scaphoid could no longer be accommodated in the fossa and impacted on the radial styloid.

 

Proximal row carpectomy

 

 

Although not all surgeons routinely perform a radial styloidectomy in the setting of a proximal row carpectomy, a recent cadaveric study demonstrated that radial deviation after proximal row carpectomy was

limited by impingement of the trapezoid on the radial styloid.6

 

PATIENT HISTORY AND PHYSICAL FINDINGS

 

Patients with clinically significant radial styloid arthritis or impingement frequently complain of pain along the dorsoradial aspect of the wrist that is exacerbated by extension of the wrist or gripping activities. They may also note focal swelling or a decrease in the range of motion.

 

A complete physical examination of the radiocarpal, the midcarpal, and the first carpometacarpal joints is necessary to assess for associated conditions and to rule out alternative diagnoses.

 

Styloid impingement typically causes radial-sided wrist pain that is exacerbated by radial deviation, extension, and axial loading of the wrist.

 

Physical findings of styloid impingement are centered around the anatomic snuffbox (FIG 4).

 

 

The anatomic snuffbox is triangular, with its radial border formed by the extensor pollicis brevis tendon, its ulnar border by the extensor pollicis longus tendon, and its proximal border by the dorsal rim of the distal radius at the level of the styloid. The waist of the scaphoid and a small segment of the trapezium are palpable in the floor of the snuffbox, more readily with ulnar deviation.

 

 

 

FIG 4 • Meticulous and systematic physical examination of this region can rule out diagnoses other than radial styloid impingement. RS, radial styloid; S, scaphoid; Tm, trapezium; Td, trapezoid; MC-I, thumb metacarpal.

 

 

Focal tenderness and synovitis along the proximal edge of the snuffbox made worse by forced radial deviation and extension may be indicative of styloid impingement.

 

More diffuse tenderness, synovitis, and global limitations of motion may be indicative of a more advanced stage of posttraumatic arthritis or an inflammatory process (ie, rheumatoid arthritis, gout, pseudogout), which would preclude the success of an isolated radial styloidectomy.

 

IMAGING AND OTHER DIAGNOSTIC STUDIES

 

Plain radiographs of the wrist

 

 

 

To diagnose and stage SNAC and SLAC (FIG 5) To rule out scaphoid fracture or other acute injury

 

 

 

FIG 5 • Impingement of the flexed distal pole of the scaphoid nonunion against the radial styloid leading to arthritic changes.

 

 

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Stress radiographs (clenched fist and radial-ulnar deviation posteroanterior) of the wrist can yield information concerning dynamic impingement between the scaphoid and the radial styloid.

 

 

DIFFERENTIAL DIAGNOSIS

De Quervain stenosing tenosynovitis: Tenderness usually extends along the extra-articular component of the radial styloid, proximally and radially over the first dorsal compartment. A positive Finkelstein test is highly suggestive of this disorder.

Scaphoid-trapezoid-trapezium arthritis: focal tenderness in the distal ulnar aspect of the snuffbox under the extensor pollicis long tendon along the axis of the second metacarpal

Thumb carpometacarpal instability or arthritis: tenderness distal to the anatomic snuffbox that is worsened by loading of the thumb ray (carpometacarpal grind test)

Scaphoid fracture: After an acute injury, advanced imaging (bone scan or magnetic resonance imaging [MRI]) may be required to rule out an acute scaphoid fracture.

Preiser disease

Inflammatory arthritis (ie, rheumatoid arthritis, gout, pseudogout) Radial sensory neuritis or neuroma

Tenosynovitis of the extensor carpi radialis longus and brevis

Not uncommonly, styloid impingement coexists with other diagnoses, especially basilar thumb arthritis and de Quervain stenosing tenosynovitis.

 

NONOPERATIVE MANAGEMENT

 

Individuals with chronic SLAC or SNAC wrist arthritis frequently present with acute pain after a recent injury.

After obtaining an accurate medical history of prior injury and radiographic assessment, the chronicity of the problem is usually evident.

 

 

In this situation, a course of conservative treatment with activity modification, nonsteroidal anti-inflammatory drugs, rest in a forearm-based thumb spica splint, and selective corticosteroid injection in the radial styloid area is appropriate.

 

If the arthritic changes are truly isolated to the area of articulation between the scaphoid and the styloid, the surgeon may elect earlier operative intervention with the theoretical goal of slowing or preventing progressive symptomatic arthrosis and the need for a more extensive reconstructive procedure.

 

SURGICAL MANAGEMENT

 

Isolated radial styloidectomy is a limited procedure to treat the early stage of progressive posttraumatic arthritis.

 

 

It cannot be expected to prevent its pathologic progression.

 

It can also be employed as a temporizing solution in a lowdemand individual or in a patient unfit or unwilling to undertake a more extensive procedure and postoperative rehabilitative course.

 

 

In that instance, patient expectations with respect to motion and pain relief must be assiduously managed.

 

Arthroscopic radial styloidectomy has the theoretical advantages of being minimally invasive and allowing more precise control of the level of bony resection to minimize injury to the palmar radiocarpal ligaments. In addition, arthroscopic evaluation of the radiocarpal and midcarpal joints can allow for diagnosis and treatment

of concomitant intra-articular pathology.22

 

Preoperative Planning

 

Precise radiographic assessment and patient selection are critical in ensuring a good outcome. The surgeon must review all radiographic studies and the severity, characteristics, and nature of the patient's symptoms and physical findings.

 

In some cases, final staging of the severity of articular degeneration can be made only by direct visualization with diagnostic wrist arthroscopy (FIG 6). In situations where there is incompetency of the RSC ligament (eg, rheumatoid arthritis, gout, pseudogout) radial styloidectomy may be contraindicated in that it might cause ulnar translocation of the carpus. An isolated radial styloidectomy or a more extensive reconstructive procedure can be done at the time of arthroscopy or at a later time, after the implications of the arthroscopic findings are discussed with the patient.

 

Positioning

 

The patient is positioned supine on a stretcher with an attached hand table and the arm centered on the hand table with the shoulder abducted 90 degrees. A mini-fluoroscopy unit is draped in a sterile fashion and placed in a plane perpendicular to the hand table.

 

For arthroscopic procedures, the arm is stabilized to the hand table with a strap that allows countertraction.

 

 

The shoulder is abducted 90 degrees, the elbow is flexed 90 degrees, and finger traps are placed on the index and middle fingers.

 

The forearm is suspended in a standard wrist traction tower with 8 to 12 pounds of traction employed.

 

A mini-fluoroscopy unit is draped in a sterile fashion and placed in a plane parallel to and above the hand

table.

 

 

 

FIG 6 • Arthroscopic findings of full-thickness cartilage loss in the entire scaphoid facet (dashed line) and proximal pole of the scaphoid as viewed from the dorsal 3-4 portal. These degenerative changes were not readily apparent on plain radiographs. An isolated radial styloidectomy cannot be expected to confer pain relief in this instance.

 

 

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Alternatively, the hand can be suspended via finger traps using a nonsterile overhead traction boom (ie, an arthroscopic shoulder holder); with this method, the wrist traction tower will not be an impediment to intraoperative fluoroscopic assessment (FIG 7).

 

Approach

 

A radial styloidectomy can be performed in conjunction with other reconstructive procedures such as proximal row carpectomy, intercarpal fusion, or bone grafting for a scaphoid nonunion.

 

 

In these instances, the primary procedure usually requires wide exposure through a standard dorsal approach to the wrist.

 

An isolated styloidectomy can be performed through a limited radial incision.

 

An arthroscopic styloidectomy can be performed through standard arthroscopic portals.

 

 

 

FIG 7 • An alternative arthroscopic setup can be useful. A nonsterile overhead traction boom (an arthroscopic shoulder holder) is used from the contralateral side of the operating room table to suspend the limb via finger traps with countertraction provided by a strap on the arm. With this method, the fluoroscopic images of the wrist can be obtained without being obscured by the arthroscopic wrist tower.

 

 

TECHNIQUES

• Open Radial Styloidectomy

  Palpate the distalmost aspect of the radial styloid on the volar radial aspect of the wrist. Make an incision from that point for 2 or 3 cm proximally and obliquely between the first and second extensor compartments (TECH FIG 1A).

  Alternatively, a transverse incision may provide a more cosmetically pleasing scar but also may limit exposure.

  At this level, there will be arborization of the terminal branches of the radial sensory and lateral

  antebrachial cutaneous nerves in the subcutaneous tissue.2 Use blunt dissection and gentle retraction to expose the first and second compartments.

  Distal placement of the incision may place the dorsal branch of the radial artery at risk and should be recognized.

  Incise the extensor retinaculum in the 1-2 interval and expose the radial styloid by subperiosteal dissection. Alternatively, the radius can be approached through the floor of the first compartment (TECH FIG 1B).

   

  Expose the radial styloid by sharp dissection (TECH FIG 1C).

   

  Using a sharp osteotome, remove the distal 3 to 4 mm of radial styloid. The plane of the cut should be perpendicular to the articular surface (TECH FIG 1D).

   

  Fluoroscopic imaging of the level of resection can be useful at this point in the procedure.

   

  A narrow malleable retractor can be placed in the radiocarpal joint to prevent damage to the scaphoid as the styloid is being resected (TECH FIG 1E).

   

  After styloidectomy, fluoroscopic examination with the wrist in radial and ulnar deviation to assess for impingement confirms adequacy of the resection level (TECH FIG 1F,G).

   

  Loosely reapproximate the periosteum with resorbable suture, allow the extensor compartments to fall back into their anatomic position, and suture the skin. A bulky dressing and volar splint holding the wrist is applied.

   

   

   

  TECH FIG 1 • Open radial styloidectomy. A. A 2- to 3-cm oblique skin incision is made between the first and second extensor compartments. Note the branches of the radial sensory and lateral antebrachial cutaneous nerves. B. The first dorsal compartment is then opened. (continued)

   

   

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  TECH FIG 1 • (continued) C. The radial styloid is extraperiosteally exposed by sharp dissection. D. An osteotome is used to resect the distal 3 to 4 mm of radial styloid. The osteotome should be angled perpendicular to the joint surface. E. The resected radial styloid is removed. F,G. Preoperative and postoperative PA radiographs of the wrist with early SNAC undergoing open radial styloidectomy. (Courtesy of Dr. John J. Fernandez.)

• Arthroscopic Styloidectomy

 

After patient positioning as previously described, insufflate the joint with 5 to 10 mL of sterile saline and establish the 3-4 portal. Outflow is achieved by placing an 18-gauge needle in the 6U interval. Perform a complete arthroscopic evaluation of the radiocarpal joint.

 

Establish the radial and ulnar midcarpal portals and perform an arthroscopic evaluation to confirm capitolunate joint preservation.

 

Place a localization needle into the styloscaphoid joint space, in the interval between the first and second compartments to localize and establish the 1-2 arthroscopic portal. Angling the needle about 24 degrees proximal to mirror the radial inclination will avoid damage to the scaphoid articular surface.

 

Confirm the adequacy of the position of this working portal by arthroscopic evaluation from the 3-4 interval. The volar radial portal can also be used interchangeably with the 3-4 portal for viewing and

instrumentation to assure complete access to the radial styloid.17

 

Develop the portal by sharp dissection through skin only and blunt dissection in the subcutaneous tissues to the capsule to prevent damage to the radial sensory nerve, the lateral antebrachial cutaneous nerve, and the radial artery. This is best accomplished by a starting point within 4 mm of the

palpable tip of the radial styloid.17

 

The full-radius resector is first placed in the 1-2 portal to débride the soft tissue radial, dorsal, and volar to the styloid so that the anticipated bone resection can be more easily defined (TECH FIG 2A). Resect the radial styloid with a 2.9-mm full-radius resector, an arthroscopic covered burr, or both. This is initiated at the radial margin of the RSC ligament and carried radially. The diameter of the burr can

be used as a gauge for the amount of bone being resected. The degenerative cartilage changes of the radial styloid facet can also serve as a useful guide to the ulnar most margin of resection that is required.

 

Intraoperative fluoroscopy is critical in the assessment of the resection level (TECH FIG 2B).

 

After completing the styloidectomy, the wrist is brought out of traction and arthroscopic and fluoroscopic assessment is used to confirm that no further carpal impingement exists. Remove the arthroscopic instruments and suture the portals. Apply a sterile bulky dressing and volar splint to the wrist and forearm.

 

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TECH FIG 2 • Arthroscopic radial styloidectomy. A.The arthroscopic burr is in the 1-2 portal and the arthroscope is in the 3-4 portal. B. Fluoroscopic image obtained during arthroscopic radial styloidectomy for scapholunate instability and secondary degeneration. Note the disruption of the line of Gilula in the proximal carpal row.

 

PEARLS AND PITFALLS
	Indications ▪ A complete history and physical examination emphasizing clinical staging is essential. The final decision to proceed with styloidectomy may require staging arthroscopy.     Insufficient or ▪ Arthroscopic visualization of the RSC ligament to prevent significant injury excessive styloid and to assure its competency resection ▪ Using the diameter of the burr as a gauge for the amount of bone resected Intraoperative fluoroscopic evaluation     Poor ▪ Convert from arthroscopic to open procedure. arthroscopic visualization

 

 

POSTOPERATIVE CARE

 

If the radial styloidectomy is performed concomitantly with another reconstructive procedure (PRC, four-corner arthrodesis, scaphoid bone grafting and fixation), the rehabilitation is dictated by the requirements of that additional procedure.

 

After either open or arthroscopic radial styloidectomy, the postoperative dressing and sutures are removed in 7 to 10 days. Early active, active-assisted, and passive motion is initiated under the guidance of a hand therapist. Usually, a removable splint is used initially for patient comfort. As the patient's symptoms permit, graded strengthening and unrestricted activities are allowed.

 

 

OUTCOMES

Barnard and Stubbins1 first described a radial styloidectomy as part of an operative treatment strategy for scaphoid nonunion in 14 patients in 1948. They thought that the styloidectomy removed impingement, enhanced exposure of the scaphoid, and provided material for bone grafting from the same operative field. Since that time, there have been no series of outcomes in the indexed English literature for outcomes after isolated open radial styloidectomy. Several reports of radial styloidectomy performed with open reduction and internal fixation of scaphoid nonunion or with triscaphe fusion have demonstrated

good pain relief but no significant improvement in range of motion.14,21

Ruch et al15 were the first to describe the use of an arthroscopic radial styloidectomy in the treatment of

avascular necrosis of the proximal pole following scaphoid nonunion. Page et al13 presented their experience with the arthroscopic technique in 22 patients to the European Federation of National Associations of Orthopaedics and Traumatology in 2003. In short-term follow-up, they reported 75% good

and satisfactory results. Levadoux and Cognet11 reviewed their results in 12 patients with SLAC I and SLAC II arthritic changes with average follow-up of 39 months. They showed an 18% increase in grip strength and high patient satisfaction; 80 % of their patients experienced complete relief of their wrist

pain. Birman et al5 performed arthroscopic radial styloidectomy combined with arthroscopic débridement and selective anterior and posterior interosseous neurectomies in advanced SLAC wrist (II and III) in an effort to delay or avoid salvage procedures in eight wrists. At an average of 28 months post procedure, they had maintained good motion and had a 71% satisfaction rate. The authors, however, did caution that this is best thought of as an intermediate procedure to relieve pain and preserve motion.

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Radial styloidectomy is most often performed as a limited procedure to address posttraumatic arthritis of the wrist early in its pathogenesis. Although it can provide long-lasting symptomatic relief, it cannot be expected to halt the progression of the arthritis. A successful radial styloidectomy could be one in which a more extensive reconstructive procedure was delayed by several years.

 

COMPLICATIONS

Incomplete resection leading to persistent pain

Excessive resection leading to extrinsic ligament incompetence and wrist instability with ulnar

 

translocation

Nerve injury to the terminal branches of the radial sensory nerve or lateral antebrachial cutaneous nerve Arthrofibrosis

Infection

Complex regional pain syndrome

 

 

REFERENCES

1. Barnard L, Stubbins SG. Styloidectomy of the radius in the surgical treatment of nonunion of the carpal navicular: a preliminary report. J Bone Joint Surg Am 1948;30(1):98-102.

    

    

2. Beldner S, Zlotolow DA, Melone CP Jr, et al. Anatomy of the lateral antebrachial cutaneous and superficial radial nerve in the forearm: a cadaver and clinical study. J Hand Surg Am 2005;30(6):1226-1230.

    

    

3. Berger RA. The ligaments of the wrist. A current overview of anatomy with considerations of their potential functions. Hand Clin 1997;13:63-82.

    

    

4. Berger RA, Landsmeer JM. The palmar radiocarpal ligaments: a study of adult and fetal human wrist joints. J Hand Surg Am 1990;15(6):847-854.

    

    

5. Birman MV, Danoff JR, Rosenwasser MP. Arthroscopic wrist debridement and radial styloidectomy for late stage scapholunate advanced collapse wrist. Presented at the Arthroscopy Association of North America annual meeting, Orlando, FL, May 2012.

    

    

6. Blankenhorn BD, Pfaeffle HJ, Tang P, et al. Carpal kinematics after proximal row carpectomy. J Hand Surg Am 2007;32(1):37-46.

    

    

7. Blevens AD, Light TR, Jablonsky WS, et al. Radiocarpal articular contact characteristics with scaphoid instability. J Hand Surg Am 1989;14(5):781-790.

    

    

8. Burgess RC. The effect of rotatory subluxation of the scaphoid on radio-scaphoid contact. J Hand Surg Am 1987;12(5 pt 1):771-774.

    

    

9. Inoue G, Sakuma M. The natural history of scaphoid non-union. Radiographical and clinical analysis in 102 cases. Arch Orthop Trauma Surg 1996;115:1-4.

    

    

10. Kalainov DM, Cohen MS, Sweet S. Radial styloidectomy. In: Geissler WB, ed. Wrist Arthroscopy. New York: Springer-Verlag, 2005:134-138.

     

     

11. Levadoux M, Cognet JM. Arthroscopic styloidectomy [in French]. Chir Main 2006;25(suppl 1):S197-S201.

     

     

12. Nakamura T, Cooney WP III, Lui WH, et al. Radial styloidectomy: a biomechanical study on the stability of the wrist. J Hand Surg Am 2001;26(1):85-93.

     

     

13. Page RS, Waseem M, Stanley JK. Clinical outcome of arthroscopic radial styloidectomy. J Bone Joint Surg Br 2004;86B:280.

     

     

14. Rogers WD, Watson HK. Radial styloid impingement after triscaphe arthrodesis. J Hand Surg Am 1989;14(2 pt 1):297-301.

     

     

15. Ruch DS, Chang DS, Poehling GG. The arthroscopic treatment of avascular necrosis of the proximal pole following scaphoid nonunion. Arthroscopy 1998;14:747-752.

     

     

16. Siegel DB, Gelberman RH. Radial styloidectomy: an anatomical study with special reference to radiocarpal intracapsular ligamentous morphology. J Hand Surg Am 1991;16(1):40-44.

     

     

17. Slutsky DJ. Wrist arthroscopy. In: Wolfe SW, Pederson WC, Hotchkiss RN, et al, eds. Green's Operative Hand Surgery. Philadelphia: Elsevier, 2011:709-741.

     

     

18. Vender MI, Watson HK, Wiener BD, et al. Degenerative change in symptomatic scaphoid nonunion. J Hand Surg Am 1987;12(4):514-519.

     

     

19. Viegas SF, Patterson RM, Ward K. Extrinsic wrist ligaments in the pathomechanics of ulnar translation instability. J Hand Surg Am 1995;20(2):312-318.

     

     

20. Viegas SF, Yamaguchi S, Boyd NL, et al. The dorsal ligaments of the wrist: anatomy, mechanical properties, and function. J Hand Surg Am 1999;24(3):456-468.

     

     

21. Watson HK, Ballet FL. The SLAC wrist: scapholunate advanced collapse pattern of degenerative arthritis. J Hand Surg Am 1984;9(3):358-365.

     

     

22. Yao J, Osterman AL. Arthroscopic techniques for wrist arthritis (radial styloidectomy and proximal pole hamate excision). Hand Clin 2005;21:519-526.