Diagnostic wrist arthroscopy has changed our ability to understand the painful wrist.
Therapeutic wrist arthroscopy has revolutionized the treatment of many wrist conditions.
Few advances in hand surgery have been more exciting than wrist arthroscopy. Wrist arthroscopy allows for a minimally invasive approach, enabling the surgeon to look at the “black box” of wrist pain and arrive at a definitive diagnosis. It permits direct visualization of intra-articular pathology that previously could only be indirectly assessed with physical examination and imaging studies. Like arthroscopy in other joints, wrist arthroscopy was first used as a diagnostic tool to gain a deeper appreciation of intra-articular pathology. More recently, it has been used to treat that pathology with a minimally invasive approach. Aside from its diagnostic role, the prime indications for therapeutic wrist arthroscopy are (1) the treatment of triangular fibrocartilage (TFC) complex tears; (2) the treatment of intra-articular wrist ligament injury; (3) the treatment of intra-articular distal radius and scaphoid fractures, (4) ganglion resection, and (5) salvage procedures such as hamate chondroplasty, radial styloidectomy, and proximal row carpectomy ( Box 77-1 ). This chapter covers some of these procedures in detail. Clearly, wrist arthroscopy has become the gold standard for both diagnosis and treatment of many causes of intra-articular wrist pathology.
Evaluation and Treatment of Chondral Lesions
Loose or foreign body removal
Triangular Fibrocartilage Lesions
Repair peripheral tear
Arthroscopic wafer procedure
Evaluation and Treatment of Carpal Instability
Arthroscopic reduction and internal fixation
Arthroscopic Treatment of Fracture
Dorsal Ganglion Resection
WRIST CONTRACTURE RELEASE
ARTHROSCOPIC SALVAGE PROCEDURES
Proximal row carpectomy
To safely view the wrist and avoid iatrogenic injury requires distraction to expand the wrist joint spaces ( Fig. 77-1 ). The standard portals are dorsal and named in relation to the extensor compartment intervals ( Fig. 77-2 ). A minimum of three portals are needed to adequately examine the radiocarpal and midcarpal joints. The workhorse portal, the 3-4, enters the wrist at the scapholunate interval and provides access to most of the radiocarpal joint ( Fig. 77-3 ) Given the curvature of the radiocarpal space, an ulnar portal, 4-5 or 6-R, is necessary to assess the lunatotriquetral (LT) junction, the pisotriquetral joint, and the radial dorsal aspect of the wrist. The midcarpal joint is often a seat of wrist pathology and can be a key for interpreting the joint reaction to ligament injury. Thus radial and ulnar midcarpal portals should be standard in any diagnostic wrist arthroscopy. Distal radioulnar joint arthroscopy can be done but is not a routine part of diagnostic arthroscopy unless loose bodies or synovitis of this joint is suggested. A carefully systematic approach allows visualization of the critical structures of wrist joint anatomy ( Box 77-2 ).
Long radiolunate ligament
Vascular fat pad
Intrinsic scapholunate ligament
Short radiolunate ligament
Proximal articular surfaces: scaphoid, lunate, triquetrum
Facets of distal radius
TFC: central and peripheral
Ulnolunate and ulnotriquetral ligaments
Dorsal radiocarpal ligament
Distal articular surfaces of scaphoid, lunate, triquetrum
Proximal articular surfaces of capitate, hamate, trapezoid, trapezium
Scaphotrapezial, scaphocapitate, arcuate, triquetrocapitate, triquetrohamate
Space of Poirier
Distal radioulnar joint
Undersurface of TFC
TFC, triangular fibrocartilage.
A number of studies have identified the diagnostic superiority of wrist arthroscopy over advanced imaging techniques such as arthrography, CAT scan, and MRI. Even with the higher-resolution scanners, this is still true for intrinsic ligament pathology, cartilage lesions, and peripheral TFC tears. Diagnostic limitations exist, in that not all identifiable pathology is symptomatic. Any arthroscopic finding must be correlated to the clinical presentation. It is always the combination of the clinical exam, diagnostic imaging, and the arthroscopic findings that leads to a predictable treatment algorithm for wrist disorders.
Role of Arthroscopy in the Treatment of Triangular Fibrocartilage Lesions
Injury of the TFC is frequently implicated as a cause of wrist pain. Wrist arthroscopy has become standard in the diagnosis and treatment of these injuries ( Fig. 77-4 ). The anatomy, biomechanics, mechanism of injury, as well as the clinical presentation and diagnostic imaging were presented in previous chapters.
Several classification systems have been described, , but we have found the one by Palmer , to be the most useful. He divides the injuries into two basic categories: traumatic (type I) and degenerative (type II). Traumatic lesions are classified according to the location of the tear within the TFC complex ( Fig. 77-5 ). Degenerative lesions are associated with positive ulnar variance and often have associated damage to surrounding structures such as the LT ligament and articular surfaces of the lunate triquetrum, and distal ulna.
Indications for Arthroscopic Treatment
Initial treatment of most acute TFC injuries is by immobilization. Care should be taken to rule out any significant instability of the distal radioulnar joint as well as associated injuries such as subluxation of the extensor carpi ulnaris (ECU) tendon. If routine radiographs are negative and instability is not present, immobilization for 4 weeks is recommended. A peripheral tear should heal because of its good vascularity. In some patients, the judicious use of a steroid injection to quiet down local synovitis or ECU tendinitis, as well as a short course of wrist therapy, may also be helpful. Many central tears may also become asymptomatic even though they do not heal. In a recent study, we followed the natural history and treated asymptomatic TFC tears. The study shows that traumatic TFC tears with neutral ulnar variance did not tend to worsen over time and were asymptomatic at an average of 9.5 years. By contrast, a TFC tear associated with positive ulnar variance did worsen with time both symptomatically and radiologically. Studies by Mikic and others have revealed age-related TFC perforations. In Mikic’s studies, there were no TFC perforations in wrists of individuals younger than 30 years. After the third decade, however, a linear progression of perforation with age was evidenced by the fact that all specimens from patients older than age 50 were found to have a TFC perforation. These anatomic findings support the concept that a defect in the central portion of the TFC can occur without symptoms. It is important to keep this fact in mind before attributing patient’s symptomatic pain fully to an observed perforation on an imaging study.
Indications for arthroscopic TFC surgery are (1) a proven or suggested TFC injury with (2) ulnar wrist symptoms that are sufficient to interfere with activities; and (3) failure of a nonoperative treatment program of rest, immobilization, and anti-inflammatories. Generally, we wait a minimum of 3 to 4 months after the initial injury.
Arthroscopic Treatment of Class I-A Lesions
Class I-A lesions are isolated central tears of TFC without instability. For patients with neutral or negative ulnar variance who have had no relief from nonoperative treatment, arthroscopic-limited debridement of the unstable portion of the tear gives excellent relief of symptoms ( Fig. 77-6 ). Open debridement is an option if arthroscopic treatment is not available.
The biomechanical effect of excision of the central portion of the TFC has been examined. , The excision of up to two thirds of the central portion of the TFC with maintenance of the dorsovolar and radioulnar ligaments and the ulnocarpal ligaments had no demonstrable effect on forearm axial load transmission or stability. Removal of greater than two thirds of the disc or injury to the ligamentous portions destabilizes the distal radioulnar joint. Adams has emphasized that the peripheral 2 mm of the TFC must be maintained to avoid such stability problems.
Arthroscopic Treatment of Class I-B Lesions
The diagnosis of a chronic I-B peripheral tear can be difficult. Clinically, aside from ulnar wrist pain and a positive TFC stress test, there is often the suggestion of mild distal radioulnar joint instability. In the isolated lesion without ulnar styloid fracture, plain radiographs are normal. Distal radioulnar joint arthrography has been the most accurate modality, identifying 60% of such tears compared with MRI. The use of gadolinium injections may enhance the sensitivity of the MRI. ,
Arthroscopy, however, is ideal in defining the peripheral lesion. From a viewing radial portal, the examiner may note synovitis peripherally and after debriding this, the peripheral tear may become obvious. The pathognomic finding is a loss of the normal tension of the TFC ( Fig. 77-7 ). Using a probe brought through an ulnar portal, the tension in the TFC is palpated. As Hermansdorfer and Kleinman have described, the tension in the TFC should be taut like that of a drumhead or a trampoline. If the probe sinks into the TFC, as if into a feather bed, then a peripheral tear should be considered.
One caveat in treating type II-B peripheral tears is the fact that many of such lesions are associated with subluxation of the ECU tendon. The fibrous floor of the ECU sheath is intimate with the peripheral TFC. With a hypersupination of the wrist both structures can be simultaneously torn. Melone and Nathan defined a continuum of injury on the ulnar side of the wrist beginning with ECU sheath through the peripheral portion of the TFC continuing on through the ulnar extrinsic ligaments and LT ligaments. Thus, ECU subluxation accompanying a peripheral tear represents an early stage of this sequential injury pattern. Treatment requires not only arthroscopic repair of the peripheral TFC tear but open reconstruction of the ECU sheath. In multiple studies it is now clear that arthroscopic repair compares favorably with the open technique.
There are two main techniques of arthroscopic repair. They both share an outside-to-inside approach but differ in the direction of that approach. Poehling has popularized Tuohy’s needle technique, directing the sutures from the radial side of the wrist across the tear. The sutures are retrieved ulnarly and tied. A concern of this repair technique is that the position of the counterincision and the exit point are somewhat difficult to control. Complications relative to irritation of the dorsoulnar sensory nerve have been reported. Currently, we favor an out–in technique from the ulnar side as originated by Whipple.
Arthroscopic Treatment of Class I-C Lesions
Class I-C lesions involve disruption of the TFC from the ulnar extrinsic ligament complex. Clinically, the patient may show a carpal supination deformity. Imaging techniques are not useful. Arthroscopically, the diagnosis is made by a loss of tension in the ulnar extrinsic ligaments as well as the easy and direct visualization of the pisotriquetral joint. Tay and colleagues have described a positive fovea sign associated with a split lesion extending across the ulnar extrinsic ligaments.
Authors’ Preferred Method
If the defect in the ulnar extrinsic ligaments is reparable, we will make a small 1-cm incision volar to the ECU tendon in the area of the triquetral snuff-box. Care is taken to avoid injury to the dorsal ulnar sensory nerve or volar ulnar neurovascular structures. The technique is similar to the out–in repair of the peripheral TFC lesion. Needles are passed through the capsule through the defect in the ulnar extrinsic ligaments. The looped 2-0 polydioxanone sutures (PDS) are then brought out and tied at the capsule level. When this lesion is present and repaired arthroscopically, it is often common to also reef the dorsal ulnar portion of the TFC ligament as described for the class I-B lesion.
Arthroscopic Treatment of Class I-D Lesions
Class I-D lesions involve radial detachment of the TFC from the sigmoid notch to the distal radius ( Fig. 77-8 ). Although not in Palmer’s classification, this lesion can be further categorized as one that occurs in isolation and is associated with a distal radial fracture. This is in fact the most common peripheral tear observed in distal radial fracture. Normally, the articular cartilage of the radius continues around the medial corner and into the sigmoid notch. The TFC originates from this articular location. Given this cartilage barrier, vascular studies suggest that the potential for healing of such a radial tear is poor. However, if this cartilage is disrupted by fracture or mechanically, and the attachment site occurs on vascularized bone, then healing can occur. Cooney and colleagues have reported excellent results of radial-sided TFC repairs done openly. Arthroscopic repair techniques have been described by Sagerman and Short, Jantea and co-workers, and Trumble and associates.
Most isolated tears, not associated with instability, are best treated by simple debridement similar to that for a I-A lesion.
Type II: Degenerative Triangular Fibrocartilage Lesions
Degenerative tears are related to chronic overloading of the ulnar side of the wrist. The primary pathology is not in the TFC but rather the result of chronic ulnar abutment or impaction. Once symptomatic, the problem is progressive, and deterioration occurs over time. For this reason, we recommend surgical correction in sufficiently symptomatic patients. The ulnar impaction may be primary or secondary. Wrists with neutral or positive ulnar variance demonstrate tears or perforations 73% compared with only 17% in specimens with negative ulna variance have shortened. Secondary causes are generally traumatic and include distal radial fractures that. Short and colleagues have correlated increases in the dorsal tilt of the distal radius with forces transmitted to the distal ulna during axial loading. The ulnar impaction may also be dynamic, being present only on load activities such as grip or forceful rotation. Thus, a patient with static neutral or even negative ulnar variance could dynamically have ulnar abutment. Arthroscopy plays a definite role in the treatment of primary ulnar impaction, whereas in secondary abutment, ulnar shortening osteotomy is often required.
In Palmer’s schema, the progressive degenerative changes of ulnar abutment are subdivided into five categories Box 77-3 .
Degeneration of the horizontal portion of the TFCC w/o perforation
Degeneration of the horizontal portion of the TFCC w/o perforation
+ lunate or ulnar chondromalacia (or both)
Full-thickness perforation of the horizontal portion of the TFCC
+ lunate or ulnar chondromalacia (or both)
+ lunate or ulnar chondromalacia (or both)
+ LT ligament perforation
+ lunate or ulnar chondromalacia (or both)
+ LT ligament perforation
+ ulnocarpal arthritis
LT, lunatotriquetral; TFCC, triangular fibrocartilage complex; w/o, without.
Diagnosis of a degenerative tear should be considered in an older patient who complains of nontraumatic ulnar-sided wrist pain. Physical examination reveals tenderness over the distal ulna, which increases with rotatory motion and loading of the wrist. TFC compression test is often positive. Other provocative maneuvers such as the shuck test should be performed to assess the LT ligament stability. Distal radioulnar joint compression test may be positive if arthritis is present in this joint. Measurement of grip strength in pronation and supination may also be helpful.
As mentioned previously, ulnar variance radiographs are critical ( Fig. 77-9 ). Reservations relative to any cystic changes present on the ulnar aspect of the lunate or in the ulnar head should be recorded as well as the presence of any incongruency or arthritis of the distal radioulnar joint. Arthrography is seldom used now, but radiocarpal injection can demonstrate the central TFC tear, and midcarpal arthrography the LT perforation.
MRI has been applied to the diagnosis of ulnar impaction. These symptomatic patients have focal signal intensity changes in the ulnar part of the lunate. Signal abnormality should not be confused with Kienböck’s disease. Imaeda and colleagues noted focal abnormal signal intensity on the ulnar aspect of the lunate in 87% of patients with ulnar impaction, 43% showed similar changes on the triquetrum, and 10% on the radial aspect of the ulnar head. Following surgical correction, the signal intensity often returns to normal. MRI can also reveal tears in the TFC with a high degree of accuracy, but is not sensitive to alterations in the LT ligament.
Diagnostic arthroscopy is the best way of staging the ulnar impaction lesion. Arthroscopy can directly evaluate the chondral surfaces for evidence of fibrillation or more severe chondral changes not visible on current imaging techniques. The TFC lesion is generally central and ragged relative to the more linear traumatic tear ( Fig. 77-10 ). The lunatotriquetrum and stability of the LT joint should be assessed not only from radiocarpal but also from midcarpal portals.
The primary goal in the treatment of ulnar impaction is to unload or decompress the ulnar carpus and ulnar head. This decompression can be accomplished by ulnar shortening osteotomy, partial ulnar head resection, or ulnar salvage procedures. Ulnar shortening osteotomy was originally devised by Milch in 1941. The Mayo clinic group rekindled an interest in ulnar recession, and now this procedure has been modified by the use of rigid fixation methods. Partial ulnar head resection, the so-called wafer procedure, removes the positive very distal portions of the ulna while leaving the distal radioulnar joint intact. Feldon and coworkers devised the open-wafer technique, and it is now often performed arthroscopically. , Distal radioulnar joint salvage procedures, such as a modified Darrach, hemiresection interposition procedure, are best used when arthritis is present in the distal radioulnar joint.
Type II: D and E
These are the end stages of the ulnar impaction syndrome and represent disruption of the LT ligament with varying degrees of instability. Following the arthroscopic debridement of the TFC as described for the II-C lesion, a careful evaluation of the LT interval is done from both the radiocarpal and midcarpal joints. If the ligament is frayed but the midcarpal joint shows no significant stepoff at the LT interface and there are no chondromalacic changes on the hamate, then an arthroscopic wafer procedure is performed similar to that for a type II-C lesion. This is particularly true in the older individual.
If evidence of LT instability, such as fraying of the ulnar extrinsic ligaments, significant translation of the LT interface in the midcarpal joint, and chondromalacic changes on the hamate interface is noted, then an ulnar shortening osteotomy is preferred. The frayed portions of the LT ligament are debrided, synovitic changes in the radiocarpal and midcarpal joint debrided, and in some cases a chondroplasty of the hamate is performed. If significant arthritic changes are present at the distal radioulnar joint, then salvage procedures are indicated.
A short arm cast is worn for 4 weeks. A graduated therapy program is then begun, with maximum improvement being reached by 4 months.
Optimal outcome of arthroscopic surgery for the degenerative type II lesions requires long-term follow-up. Results at 3 to 5 years have yielded good-to-excellent clinical results in 75% of cases.
Arthroscopy in the Treatment of Wrist Ligament Injuries
Current indications for wrist arthroscopy in assessing and treating carpal intrinsic instability are to (1) confirm a suggested clinical or imaged diagnosis; (2) define the degree of tear and the joint reaction to it, including areas of synovitis and chondromalacia; (3) stage surgical treatment based on the arthroscopic findings; and (4) treat arthroscopically with debridement or reduction and stabilization.
Studies are confirming the increased accuracy and sensitivity of wrist arthroscopy compared with wrist arthrography or MRI. It is particularly true when dual lesions are present. Weiss and associates noted that compared with arthroscopy, wrist arthrography correctly identified intrinsic ligament lesions only 60% of the time. Furthermore, arthrography cannot assess the magnitude of the tear, nor the presence of associated chondral lesions. With the improved resolution of dedicated wrist MRI coils, scapholunate tears can be identified, but predictable visualization of the LT ligament remains elusive.
Clarification of the nature of the ligamentous injury provides a more rational basis for reconstructive procedures. For example, arthroscopy reveals whether there is sufficient scapholunate ligament present to consider ligament repair and augmentation. It can be helpful in determining whether sufficient arthritis is present to preclude reconstructive procedures.
No ideal, predictable treatment for scapholunate instability exists. When the instability is subtle, the results of open operative stabilization, regardless of the method, often cause more morbidity than the original pathology. Arthroscopy has a definite role in diagnosis, but its therapeutic role remains unproven.
Recent anatomic investigations by Berger have defined the complex anatomy of the intrinsic scapholunate ligament. Dorsal and volar fibrous components are the major stabilizers, whereas the central portion is membranous and contributes very little to the ligament strength.
Currently, scapholunate intrinsic lesions can be graded based on their arthrographic and radiographic appearance , ( Box 77-4 ). In grade I lesions, the ligament is noted to be stretched and redundant but intact to palpation from the radiocarpal joint ( Fig. 77-11 ). Evaluation of the midcarpal joint shows minimal scapholunate interface instability and no reactive chondral or synovitic change ( Fig. 77-12 , Table 77-1 ). This is a dynamic instability and may be the ideal case for capsular shrinkage.
Stage 1: Hemorrhage + no SL gap
Stage 2: Probe can be introduced in SL space
Stage 3: Probe can be rotated in SL space
Stage 4: 2.7-mm scope “drive thru” SL to enter MC space
MC, midcarpal; SL, scapholunate.
|Stage I||No MC incongruency||Normal triscaphe|
|Stage II||Slight gap < 1 mm||Synovitis in triscaphe|
|Stage III||MC step-off pass trocar||Chondromalacia in triscaphe|
|Stage IV||2.7-mm scope drive-thru||Chondromalacia in triscaphe|
Grade II lesions reveal a perforation of the central or membranous portion of the ligament ( Fig. 77-13 ). Midcarpal findings reveal minimal interface instability and no reactive synovitic or chondral changes. Simple ligament debridement of the torn frayed edges is often sufficient. In separate studies and on short-term follow-up, both Ruch and colleagues and Weiss and co-workers noted improvement in 85% of their patients.
In grade III lesions, there is a perforation of the central membranous component which extends to the volar dorsal fibrous portions. Examination of the midcarpal joint reveals interface instability that admits a 2-mm probe. A reactive synovitis is also present in the scaphotrapezoid trapezial joint as well as chondral change on the distal pole of the scaphoid.
Grade IV lesions are characterized by complete scapholunate instability in which a scope can be passed freely into the midcarpal joint. This lesion is usually not amenable to arthroscopic treatment.
Lesions of the Lunatotriquetral Intrinsic Ligament
Like its counterpart, the scapholunate ligament, the LT ligament has three subportions. There are dorsal and volar fibrous stabilizers and a central membranous portion. The fibrous portion of the ligaments merge volarly with the ulnar extrinsic ligaments and dorsally with the radial–LT ligament. Chronic LT ligament tears can be subdivided into traumatic and degenerative. Partial tears of the LT ligament are more common than complete tears. Partial tears favor a limited debridement of the ligament. In complete tears, midcarpal arthroscopy through the radial midcarpal portal reveal instability of the LT interface often with associated chondral changes on the proximal pole of the hamate. These cases favor arthroscopic reduction and internal fixation. An isolated LT ligament tear does not produce a volar intercalated segment instability pattern, and when this is present it represents both intrinsic and extrinsic ligament damage, which is not amenable to arthroscopic treatment.
Degenerative Lunatotriquetral Tears
Not all LT ligament tears are traumatic. Viegas and associates showed a positive correlation between age and LT ligament tears. In wrists of patients older than 60, a 27% incidence of LT ligament tears occurred, whereas no tears were noted in patients younger than 45 years. Also supporting a degenerative cause was the finding of increased incidence of TFC tears and positive ulnar variance. As stated earlier in addressing the ulnar impaction lesion (of which the LT degenerative tear represents stages II-D and II-E), attention must be directed at decompressing the ulnar impaction. For example if an ulnar shortening osteotomy has been performed the stability of the LT interval is evaluated only after the shortening procedure. Treatment of the LT ligament then follows a protocol similar to that for the partial and complete traumatic lesions.
Role of Arthroscopy in the Treatment of the Distal Radial Fracture
Increasingly, wrist arthroscopy is seen as a valuable adjunct in the management of intra-articular distal radius fractures. It provides a visible means of assessing both the congruency of the articular surface reduction and the extent of the intercarpal soft tissue injury. Furthermore, the use of percutaneous pins aids in anatomically restoring and maintaining an articular surface reduction.
Indications for arthroscopically assisted reduction and internal fixation include intra-articular distal radial fractures with articular displacement greater than 2 mm after an attempt at closed reduction ( Fig. 77-14 ). It may also be indicated for nondisplaced intra-articular fractures or extra-articular distal radius fractures in which an associated carpal ligamentous injury is suggested. It can be used in conjunction with various fixation techniques, including percutaneous pinning, external fixation, and open reduction and internal fixation (ORIF). If a significant bone defect is noted, as commonly is seen following elevation of a die-punch fragment, limited incision bone grafting is recommended. Contraindications may include compartment syndrome, severe soft tissue injury, significant median nerve compromise, or an open joint injury.
Arthroscopy is not required in the majority of distal radial fractures. In the last 5 years at our tertiary referral center, only 15% of distal radial fractures received arthroscopy compared with 30% treated by casting or pin fixation/external fixation and to 45% requiring ORIF.
Assessment and Treatment of Associated Soft Tissue Injuries
Wrist arthroscopy has been an invaluable tool for identifying the prevalence of soft tissue intercarpal lesions associated with the distal radial fracture. Many of these lesions are difficult, if not impossible, to evaluate by radiologic techniques. Geissler and colleagues, in evaluating 60 patients with displaced radial fractures, noted that 68% had soft tissue injury of the wrist, including 43% with TFC lesions, 32% with scapholunate interosseous tears, 15% with LT ligament tears, and 20% with multiple soft tissue injuries. Chondral lesions of the carpal bones have been identified with an incidence of 23% to 44%. ,
Complete and partial scapholunate intrinsic ligament tears correlate with dorsal displacement of the radius greater than 20 degrees, radial styloid and lunate impaction fracture patterns, and static dorsal intercalated segment instability on a prereduction radiograph ( Fig. 77-15 ). There was no correlation of scapholunate tears with radial shortening or ulnar styloid fracture. When the incongruency of carpal alignment is apparent in both radiocarpal and midcarpal spaces and a probe or arthroscope can be passed from the radiocarpal to the midcarpal joint, then arthroscopic reduction and internal fixation is indicated. In our series, this occurred in 25% of the cases.