Arthroscopic treatment of acute scapholunate and lunotriquetral ligament injuries

ARTHROSCOPIC TREATMENT OF ACUTE SCAPHOLUNATE AND LUNOTRIQUETRAL LIGAMENT INJURIES MARK HENRY, MD

Acute scapholunate and lunotriquetral interosseous ligament injuries must be stabilized for anatomically correct healing to prevent progressive carpal instability. Shortcomings of reconstruction procedures place a priority on achieving a successful initial repair. The traditional repair strategy involves open reduction and internal fixation and results in significant long-term wrist stiffness. An attempt to produce less scarring with minimally invasive techniques is currently being made using arthroscopy to guide the reduction and fixation of the intercarpal relationships during repair. One of the most important aspects of managing intrinsic ligament injuries in the wrist is making an accurate evaluation of the injury magnitude and recognizing the importance of functional stability provided by the ligament. This article provides an injury grading method based on functional stress testing of the scapholunate and lunotriquetral interosseous ligaments. The details of the arthroscopic technique have not been firmly established by the limited number of authors that have reported on the subject to date. Furthermore, long-term results in high numbers of patients are not currently available to firmly establish the efficacy of arthroscopic treatment of acute perilunate injuries. KEY WORDS: ligament, wrist, instability, repair Copyright 2003, Elsevier Science (USA). All rights reserved.

Disruption of the scapholunate interosseous ligament (SLIL) a n d / o r lunotriquetral interosseous ligament (LTIL) may occur in isolation or as part of a more extensive perilunate wrist dislocation. Both ligaments may be injured to various degrees from partial to complete rupture. At the time of injury, the two carpal bones adjacent to each ligament may shift only minimally despite complete ligament rupture, shift significantly but with immediate spontaneous reduction or the patient may present with a wrist dislocation. The injury may begin at the radial aspect of the wrist and progress in an ulnar direction or vice versa depending on the precise mechanism. When a perilunate dislocation is associated with fracture of the radial styloid or one or more carpal bones, the lesion is referred to as a greater arc injury. When a perilunate dislocation is purely ligamentous, the lesion is referred to as a lesser arc injury. This report details the arthroscopic evaluation and management of the latter. The unique anatomy and properties of the intrinsic ligaments of the proximal row (SLIL and LTIL) make their effective reconstruction difficult and underscore the need for successful initial repair after injury. Patients with acute injuries that are appropriately managed may achieve primary ligament healing and possibly avoid later reconstructive procedures. 1-n The minimum treatment currently considered necessary is a reduction of the intercar-

From the Houston Hand and Upper Extremity Center, Houston, TX. Address reprint requests to Mark Henry, MD, Houston Hand and Upper Extremity Center, 1200 Binz St. #1200, Houston, TX 77004. Copyright 2003, Elsevier Science (USA). All rights reserved.

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pal relationships and pinning for 8 to 12 weeks. The treatment method of choice to accomplish this goal remains controversial. The reduction may be accomplished closed, arthroscopically or through a dorsal (+ volar) open approach. 12-14 Similarly, the management of the torn intrinsic ligaments varies from reattachment to the carpal bones with suture to reduction of the carpus without direct handling of ligamentous tissue. 15 When attempting a definitive reduction by purely closed methods, simultaneous control of scaphoid and lunate position is difficult to achieve and is not currently recommended. 16,17 Open reduction affords direct control over the carpal bones. Dorsally, the scapholunate relationship can be assessed and the dorsal component of the SLIL directly repaired. Volarly, the carpal canal can be decompressed and sutures placed in the transverse disruption of the extrinsic capsular ligaments if needed. A combined dorsal and volar approach offers the opportunity to do all of these things. Several questions then arise: Is direct visualization the most accurate w a y to assess carpal reduction? Surgeons skilled in wrist arthroscopy recognize its superior ability to assess intercarpal relationships compared with open arthrotomy. The most important and reliable visual confirmation of carpal reduction is evaluation of the scapholunate and lunotriquetral joints via the midcarpal portals. Is open handling of the ligament tissue necessary to improve the final result? One popular step in the traditional open treatment of these injuries is the placement of bone anchors at the site of ligament rupture (usually the scaphoid) and the passage of the attached sutures through the torn ligament tissue. In order for a ligament to heal back to its carpal insertion, the torn end must be well

Operative Techniques in Orthopaedics, Vol 13, No 1 (January), 2003: pp 48-55

approximated to bone. Additional measures to secure ligament to bone, beyond proper approximation, have not been shown to provide an advantage in the orthopaedic literature. It is unclear, therefore, whether ligament suture techniques provide an advantage compared with approximation of ligament tissue to bone. In addition, the intrinsic ligaments of the proximal row (SLIL and LTIL) are contained within a synovial reflection when viewed from the radiocarpal joint. It is this feature, along with the capacity for elongation to the point of functional incompetence, that allows for complete ligament failure to produce no visible tissue cleft or free edge during open evaluation of the intrinsic ligaments. Arthroscopic evaluation of functional ligament competence obviates this drawback of open evaluation of ligament integrity. The technical principles delineated here for the management of lesser arc perilunate wrist dislocation can also be used to manage isolated SLIL or LTIL injuries.

INDICATIONS SLIL and LTIL injuries that are amenable to traditional open treatment can be managed arthroscopically provided both that the surgeon has a high degree of familiarity with wrist arthroscopy and that no contraindications as delineated below are present. The technique of arthroscopic treatment is based on the principle of performing the least-invasive surgery possible to meet all the necessary goals of successful treatment. The absence of a formal surgical approach through uninjured tissue to reach the site of injury is expected to result in less postoperative stiffness. The first contraindication to purely arthroscopic management of lesser arc perilunate injuries is a free edge of torn ligament seen from the radiocarpal portal that cannot be well approximated to bone. This is expected to occur most often with injuries that present initially as dislocations requiring formal reduction in the emergency room. In this instance, at least a limited opening must be made to reapproximate the ligament to bone. The second contraindication to the arthroscopic technique is associated median or ulnar nerve injury that requires the benefit of decompression afforded by the open volar approach. Furthermore, the fluid extravasation associated with arthroscopy may worsen compartmental pressure on the nerves. In the situation of acute nerve compression, surgery would need to be performed at the time of patient presentation. Conversely, the arthroscopic technique is best performed 5 days after injury to allow for reduction of swelling and intraarticular bleeding. The third contraindication is late presentation of the patient. Although the absolute time frame in which primary ligament healing remains possible is not known, prudence dictates that the arthroscopic technique not be us6d beyond 6 weeks after the date of original injury.

PREOPERATIVE EVALUATION When patients present in the emergency room, their perilunate dislocations should be promptly reduced through a combination of direct manipulation and gentle traction

under local or regional anesthesia. Radiographs should be obtained, both to confirm reduction and to assess for previously unrecognized injuries. If the median and ulnar nerves are not acutely compressed and the injury is closed, then the patient can be treated electively. Short-arm volarbased splinting with a gentle compressive dressing should be applied with the wrist slightly extended. The patient should be instructed on strict extremity elevation, the importance of digital range of motion exercises, and the warning signs of evolving nerve compression. Some patients do not present with a wrist dislocation but with a history of trauma and a painful, swollen wrist. For these patients, a careful history regarding mechanism of injury should be obtained. Local anesthetic injected into the wrist joint can make the manual stress examination of carpal mechanics more tolerable. Physical examination maneuvers for scapholunate, lunotriquetral, midcarpal and distal radioulnar joint instability should be performed. TM If the index of suspicion is sufficiently high for a destabilizing wrist ligament injury based on a comprehensive evaluation, then an arthroscopic evaluation is appropriate. Surgery should be scheduled for between 5 and 7 days postinjury to optimize arthroscopic visualization.

SURGICAL TECHNIQUE The importance of an efficient arthroscopic set-up should not be underestimated. While draping cables from the equipment sources and monitors, keep the scope and inflow lines completely separated from the shaver and outflow lines. Each group of lines will go to one of the surgeon's two hands. Keeping the groups separate maintains a neat working environment; cord entanglement is one of the chief sources of frustration during wrist arthroscopy. I consider the 2.7-ram arthroscope too large for the wrist and exclusively use the 2.3-mm scope. The largest instrument I will place in the joint is a 2.5-ram shaver. Separate outflow portals for the radiocarpal and midcarpal joints keep visualization clear. Use of an arthroscopy pump that has settings specifically for small joint procedures further maintains a clear field of view. I routinely use a 50 mm of mercury pressure setting and have not had a complication of fluid extravasation or nerve compromise. The tabletop traction tower is cumbersome, obstructs access to the wrist, and limits imaging possibilities. Overhead boom traction mounted to the bed is versatile and is my method of choice. The arm has a pneumatic tourniquet placed high on the brachium and is restrained to the hand table just above the elbow with a foam pad and strap. Portal landmarks can be marked before the application of traction but recognize that the skin markings will shift when traction is added. I have found the following sequence to be the most efficient to establish all six points of entry into the wrist. A 1-cm transverse incision is made just distal to the radial styloid to protect cutaneous nerve branches, the radial artery, and the first compartment tendons during outflows needle placement. Radiocarpal outflow is placed in the corner of this incision. Many texts suggest the use of the 6U portal for radiocarpal outflow. This corridor is occupied by the meniscal homologue reflection of the ulnar

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Fig 1. Location of standard arthroscopic portals.

sling of the triangular fibrocartilage complex (TFCC). Cannula placement here can damage this structure and so I prefer the aforementioned radiocarpal outflow. The 3,4 portal is established next with a small skin incision only (Fig 1). Joint injection with saline before portal placement is unnecessary. The step of spreading with a hemostat as part of establishing a portal is both unnecessary and overly rough on the soft tissues. Furthermore, it makes a sloppy portal at the capsular level that will increase the amount of fluid extravasation into the subcutaneous tissues. Through a 3-ram skin incision, the blunt cannula trocar should be placed down to the capsular level and used to palpate the convexity of the scaphoid's proximal pole. A gentle "pop" through the capsule, if angled downward correctly to match the palmar tilt of the radius, will consistently create a portal without scuffing hyaline cartilage. If one palpates instead the distal edge of the radius and shoots over it like a pool cue on the table's edge, damage to the scaphoid cartilage is more likely. One trocar should be left in place as a guide to the placement of a 50

second blunt trocar in the 6R portal. I prefer the 6R portal to the 4,5 portal as the latter necessitates pushing through the ulnar-most fibers of the dorsal radiocarpal ligament. The same targeting tangential to the slope of the carpus is used to make the entry here and avoid damage to the TFCC. The 3,4 trocar is left in place and the second trocar is now used to establish the midcarpal radial portal (MCR). I have found that this portal is neither 1 cm distal to the 3,4 portal nor directly in line with it. In my experience, the portal is slightly more ulnar than the 3,4 portal and approximately 14 to 15 mm more distal. Although these discrepancies are small, they are critical to ideal portal placement and preservation of articular cartilage. The blunt trocar is used to palpate the soft spot at the three-way junction of the scaphoid, lunate and capitate. Angling down and tangential to the capitate head avoids scuffing its cartilage. This trocar is left in place and the one in the 3,4 portal is withdrawn and used to make the midcarpal ulnar portal (MCU). The confluence of the four bones (capitate, lunate, triquetrum, hamate) is sought as a soft spot for insertion. The final step is midcarpal outflow. The needle is held on the dorsum of the wrist at an angle equal to the slope of the triquetrohamate joint with the tip directly at the MCU portal. The point of entry at the ulnar border of the hand is then marked and the needle inserted. If performed correctly, the needle will slide into the triquetrohamate joint without any bony contact. By following this step-wise progression of portal and cannula placement, each one serves as a landmark to guide the placement of the next, reducing the set-up time and improving accuracy. I use simple 18-gauge needles for outflow cannulas and steristrip them to the skin to avoid loss of position. Commercially available outflow cannulas exist with specially designed tips to ensure unobstructed flow of fluid, but those that I have seen produce more soft tissue damage than simple needles. A short section of intravenous tubing is connected to the hub of each of the two outflow needles and routed to a kidney basin that sits on the hand table next to the forearm. When complete, the outflow cannulas are oriented in the coronal plane of the body giving unobstructed access to the dorsum of the wrist. One should avoid the wasted time of switching between portals more than is necessary, but no wrist arthroscopy is complete unless four different views are taken, one from each of the aforementioned portals. For arthroscopic reduction of a lesser arc perilunate injury, I start with the scope in the 3,4 portal and shaver in the 6R portal. The shaver is used to clear joint environment rapidly before moving on to the more complicated parts of the procedure. The first step is to evaluate the edge of the scapholunate ligament. If a patulous free edge is hanging down into the joint, a purely arthroscopic approach is contraindicated. In this situation, the time taken to perform diagnostic arthroscopy should be kept to a minimum since fluid extravasation makes an open approach increasingly difficult. The volar extrinsic ligaments should be evaluated (Fig 2). Some surgeons treat a dramatic rent in the volar ligaments with an open volar approach and suture repair. [ do not consider this finding an absolute contraindication to the arthroscopic technique in its own right, but a large MARK HENRY

Fig 2. The interligamentous sulcus between the radioscaphocapitate ligament on the left and the long radiolunate ligament on the right is shown. The probe can "tug" on the ligaments to test their integrity,

volar rent usually correlates with a loose edge of the intrinsic ligament. From this view, the articular disc portion of the TFCC should also be inspected, palpated for tension and treated accordingly. The details of treatment for articular disc lesions are beyond the scope of this article but are well delineated elsewhere. The next view should be scope in the 6R and right angle probe in the 3,4 portal. The purpose of this view is to evaluate the LTIL. This ligament is often further ulnar than anticipated and can therefore be difficult to visualize properly. The probe is often needed to pull back the dorsal capsule away from the carpus to improve visualization. Again, the finding of a loose free edge must be sought. The final evaluation with this portal configuration concerns the integrity of the attachment of the dorsal radiocarpal ligament to the distal edge of the lunate and scaphoid. 19 The next portal configuration is scope in the MCR and the shaver in the MCU. The midcarpal joint is debrided until a clear joint environment is established. The probe is then inserted into the MCU to lie directly over the lunotri-

quetral (LT) interval. Grading the severity of injury is perhaps the most important step in the entire procedure. Grading the degree of LTIL disruption is done using a dynamic stress examination (Table 1). The scope and probe portals are reversed for grading the SLIL disruption. The anatomy and function of the intrinsic ligaments are complex. 2~ The dorsal and volar portions are true ligaments that control rotation, translation, and distraction between the carpal bones. 22,23 The proximal portion is membranous and composed of fibrocartilage. A combination of external manual pressure and intraarticular levering with the arthroscopic probe are used to maximally stress the relationships between each pair of carpal bones (SL and LT; Figs 3 and 4). The carpal stretch test was described by Yamaguchi based on studies where 5 kg of traction produced a radiographic scapholunate longitudinal step-off in 6 of 11 specimens after sectioning of the palmar half of the SLIL but in 10 of 11 specimens after complete SLIL division. 24 In m y protocol, four motions are tested: 1) proximal to distal distraction as in an arthroscopic version of the carpal stretch test; 2) dorsal to volar translation; 3) rotation along an axis joining the two bones; and 4) diastasis or direct separation along this same axis. Each of these shifts in position is graded as minimal, moderate, or marked. These four motions of dynamic instability by arthroscopic stress examination are pooled to reach an overall grade of functional instability (Table 1). This functional instability or ligament incompetence can occur either without (A) or with (B) a free edge of torn tissue that creates a communicating defect between the midcarpal and radiocarpal joints. Several technical points deserve emphasis. One can falsely assume that a gap exists between the lunate and triquetrum when the lunate has separate articular facets for the capitate and hamate (ie, a type II lunate). In this case, the steep drop-off that is present between the lunate's capitate facet and its hamate facet takes the appearance of a gap. This error is made by not driving the scope far enough in an ulnar direction to detect the difference between a type II lunate and a true gap in the lunotriquetral interval. The far volar and dorsal margins at each interval diverge and will allow probe placement between carpal bones with normal ligament tension in some patients. The

T A B L E 1. Arthroscopic Classification of Intrinsic Ligament Instability Average of three Midcarpal Stress Shift Tests: Distraction, Translation,

G rade

Diastasis

Rotation

Treatment

I

Volar opening of 2.3 mm,

Less than 10% shift

Partial tear does not require pin stabilization

II

no dorsal opening 2.3 mm or greater diastasis, both dorsally and volarly

Shifts between 10-25%: A: radiocarpal view, ligament reduced to normal bed B: radiocarpal view, ligament free

A: arthroscopic repair with early mobilization B: limited open direct anchor repair of ligament edge

edge not reduced 2.5 mm or greater diastasis

Shifts > 25%: A: radiocarpal view, ligament reduced to normal bed B: radiocarpal view, ligament free

A: arthroscopic repair, no early mobilization owing to

damaged secondary stabilizing ligaments B: limited open direct repair of ligament edge

edge not reduced Classification used at our center for grading wrist instability patterns that are amenable to arthroscopic treatment. TREATMENT OF ACUTE SCAPHOLUNATE AND LUNOTRIQUETRAL LIGAMENT INJURIES

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Fig 3. The "drive-thru" sign. A cannula is shown passing through the intercarpal space from midcarpal to radiocarpal joint.

midpoint of the intercarpal space, however, only allows probe insertion with pathologic ligamentous laxity. If no contraindications for continuing with the arthroscopic method were identified after radiocarpal arthroscopy, (ie, loose, free edge of intrinsic ligament protruding into the radiocarpal joint), then the 1 cm w o u n d at the radial side is accessed with Ragnell retractors to protect the nerves, vessels, and tendons. Two 0.045-inch Kirshner wires are placed into the scaphoid. I use a 14-gauge angiocath around the wires as a drill sleeve for additional protection of soft tissues. The two pins must achieve sufficient separation from each other to constitute distinct points of fixation. This will afford adequate control of the scapholunate relationship and is my configuration of choice. If this cannot be achieved, a third pin across the scaphocapitate joint would be necessary for adequate stability. The pins are prepositioned in the scaphoid but not

Fig 4. Marked instability with respect to both longitudinal distraction and rotation can be seen. 52

yet passed across the lunate. If LT interval instability exists as well, pins are prepositioned in the triquetrum for subsequent passage across this interval (Fig 5). At this point the reduction maneuver is performed. A considerable amount of mobility exists in each carpal bone after ligament injury in the wrist. When a "joystick" K-wire is inserted into a carpal bone, the surgeon directly controls the position of that bone independent of the natural relationships formed by the bone's many articulating surfaces. The potential to hold two bones in a mal-reduced position while pinning is quite high. The arthroscopic technique of indirect reduction respects each carpal bone's natural relationships with the remaining carpus and the radius and may allow for a more anatomically correct reduction. 25 A probe can be inserted into the midcarpal joint through the portal that is directly in line with the intercarpal interval (MCR portal for SLIL and MCU portal for LTIL ligament). The scope looks either radially or ulnarly from the other portal. This view gives an excellent assessment of the reduction. The proximal row bones are then manipulated by a combination of wrist position, direct external manual pressure and arthroscopic instrumentation to effect an exact anatomic reduction of the intercarpal interval (Figs 6 and 7). The idea is to use the carpal bone's contacts with adjacent surfaces to effect the reduction rather than simply holding the bone in three-dimensional space like a kabob on a stick. The pins are then advanced across the intercarpal space while the reduction is held. The arthroscope must be placed back in the radiocarpal joint at this point to evaluate the apposition of the ligament tissue to the carpal bone from which it was originally torn (Fig 8). If there is any doubt that the conditions for good ligament to bone healing exist, then a mini-open approach must be undertaken for the purpose

Fig 5. K wires are prepositioned for fixation in the scaphoid and triquetrum. The midcarpal outflow needle is in place. The effect of the "carpal stretch test" is seen in the scapholunate longitudinal distraction relationship. MARK HENRY

Fig 6. The indirect reduction technique is applied with a sharp tipped probe on the dorsal, nonarticular lip of the lunate, lifting it upward and exerting a flexion moment to restore congruency with the scaphoid in this view from the MCU portal looking radially.

Fig 8. From the radiocarpal joint, the interface between the ligament substance and the scaphoid is assessed to ensure adequate reduction of the tissue to produce healing equivalent to open bone anchor and suture placement.

ing. The tourniquet is deflated after complete dressing application. of bone anchor placement and direct ligament suture. If this is necessary, the overall magnitude of the open approach is diminished, presumably with the production of less scar tissue formation. Final pin placement is checked on image intensifier (Fig 9). Scope portals are closed with a single 4-0 Prolene or nylon suture. Short access wounds for pin placement or anchor placement are closed with the same suture in one layer only. Fluffed gauze is placed at the wrist level to accommodate swelling. The forearm and wrist are wrapped in cast padding and a fiberglass splint is applied volarly with the wrist in neutral position. Coban provides the outer layer. Caution is needed with this highly elastic material to avoid an overly tight dress-

Fig 7. A blunt tipped probe can be safely used to depress the triquetrum and control its rotation with pressure on the midcarpal articular surface in this view from the midcarpal radial portal looking ulnarly.

POSTOPERATIVE CARE AND REHABILITATION The patient is evaluated at 2 weeks postoperatively for splint and suture removal. Depending on patient reliability, a short arm cast or two-sided orthoplast removable splint is applied. Complete wrist immobilization is enforced for 8 weeks at which time the pins are removed under local anesthesia. A manipulation under brief IV

Fig 9. Pins are advanced across the scapholunate and lunotriquetral intervals and checked fluoroscopically for correct placement.

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sedation is performed just before pin removal to accelerate the rehabilitation process. Active and active-assisted range of motion begins with a "dart-thrower's" motion, which minimizes intercarpal rotation at the scapholunate joint. Continued progression to multiplanar motion occurs over the next 4 weeks. The patient is counseled to wear the protective splint except during outpatient and home therapy sessions from week 8 to 12. At 12 weeks, static progressive splinting can be used safely to overcome major loss of motion in one or more directions. Some patients demonstrate acceptable recovery of motion by this time and such splints are not a mandatory part of the rehabilitation process. Light strengthening also begins at 12 weeks postoperatively and progresses according to symptomatic tolerance over the next 3 months. Lighter patterns of functional use can begin and progress once all splinting has been discontinued. By 4 months postop, splinting should be discontinued entirely. Return to contact sports and heavy manual labor is usually permitted 6 months after surgery.

old. There were eight combined SL and LT ruptures, two combined SL and LT associated with scaphoid fractures, six isolated SL ruptures, and one LT rupture. Grading of the 27 ligament injuries was as follows: 17 grade IIIB, 4 grade IIIA, 3 grade IIB, and 3 grade IIA. An additional 18 patients with intrinsic wrist ligament injuries and associated intraarticular distal radius fractures have also been treated. The short-term (average 6 months) follow-up of these patients reveals no progression to static carpal collapse. All patients beyond 6 months have returned to their original work, report pain at less than three of 10 with application of load and have achieved over 80% of their contralateral range of motion. Grip strength has been slower to progress, but no patient has yet reached a plateau. Unfortunately, this group of patients is small and the duration of follow-up is short, limiting the conclusions that can be made about the efficacy of treatment.

RESULTS

The most serious complication in wrist trauma relates to mismanagement of the median and ulnar nerves. A critical distinction must be made between a direct contusion to the median nerve with an abnormal examination immediately following injury and the very different scenario of progressive swelling in the carpal canal with later development of subjective a n d / o r objective evidence of nerve compromise. The latter situation indicates a posttraumatic compartment syndrome of the nerve that mandates immediate decompression to avoid long-term sequelae. The former situation leaves a degree of uncertainty. Although the evidence of nerve compromise may be explained by the initial injury, this does not rule out the coexistence of sufficient ongoing swelling to exert unacceptable levels of pressure on the nerve. It is my practice to make decisions based on monofilament testing of sensibility in the involved territory. If a patient has lost the ability to perceive the 3.61-g filaments and especially the 4.31-g filaments, I operate early and ensure adequate nerve decompression. If the intention is to proceed with arthroscopic treatment of the wrist injury, endoscopic carpal tunnel release has been a successful and minimally invasive w a y to accomplish nerve decompression. In fact the procedure is easier than elective endoscopic carpal tunnel release because the synovium that normally must be removed from the deep surface of the transverse carpal ligament is not present in the traumatic setting. A final caution with respect to nerve compromise is that of extravasation of arthroscopic fluid media into the carpal canal during the procedure. If a large rent in the volar extrinsic ligament is seen on introducing the arthroscope or if at any time during the procedure considerable extravasation is witnessed, then the technique should be abandoned in favor of the more traditional open reduction and direct repair. Other arthroscopic complications are exceedingly rare but include iatrogenic damage to cutaneous nerves, tendons, or hyaline cartilage during portal creation. Finally, when percutaneous pins are inserted at the radial side of the wrist, injury to cutaneous nerve branches, radial artery, and first compartment tendons must be prevented.

Limited information is available regarding the efficacy of arthroscopic reduction and pinning techniques after intrinsic ligament injuries. Whipple has reviewed the subject and mentions his personal series of 40 patients. 26 Of note, he intentionally used multiple pins across the scapholunate interval in an attempt to create a controlled ankylosis between the bones at the center of their articulation. He states that those patients treated at both less than 3 months from injury and with less than a 3-mm gap between the scaphoid and lunate had 83% good results. Patients with either a larger gap or greater delay in treatment had 53% good results. Missing from this report is the specification of how many patients were in each of the two groups, other demographic information, or more specific grading schemes reflecting the severity injury in this cohort. Savoie treated 15 acute scapholunate and 22 acute or chronic lunotriquetral tears with arthroscopic fixation yielding 13 good or excellent results in the SL group and 21 satisfactory results in the LT group. 27The grading of the lesions or the details of the outcome assessment were not apparent in the article. Osterman treated 20 nonacute partial LT ligament instabilities with arthroscopic pinning and produced 80% good to excellent pain relief with 90% improvement in grip strength. 28 There was no description of functional stability testing of the intercarpal relationships. Another role for arthroscopy in carpal ligament injuries has been that of debridement alone. 29 In a series of 23 scapholunate tears debrided without fixation, there were 20 good or excellent results, including the only two complete tears in the group. 3~ Forty-three intercarpal tears were d6brided, yielding 66% pain relief for complete SL tears and 85% relief for partial tears. 31 For the LT tears in the series, pain relief occurred in 78% of the complete and 100% of the partial tears. I have personally applied the arthroscopic technique of reduction and pinning in a select group of patients according to the criteria specified here over the last 24 months as part of a prospective series. At this time, 17 patients have satisfied the indications. There are 12 males and 5 females. The average age is 35 years 54

COMPLICATIONS

MARK HENRY

DISCUSSION A r t h r o s c o p i c r e d u c t i o n a n d p e r c u t a n e o u s f i x a t i o n of t h e c a r p u s is a n e w a n d less i n v a s i v e t e c h n i q u e for m a n a g i n g i n t r i n s i c l i g a m e n t i n j u r i e s of t h e w r i s t . D a t a a r e c u r r e n t l y b e i n g a c c u m u l a t e d to a s c e r t a i n t h e efficacy o f this techn i q u e in a c h i e v i n g l o n g - t e r m c a r p a l s t a b i l i t y . F o l l o w - u p of 5 y e a r s o r g r e a t e r is n e e d e d in a l a r g e c o h o r t to p r o v e t h a t sound ligament healing can be obtained, and patient outc o m e s s h o u l d b e c o m p a r e d w i t h t h o s e of t r a d i t i o n a l o p e n repair techniques. Since results from the widely open procedure show significant long-term problems with pain and l i m i t a t i o n of f u n c t i o n , t h e o p p o r t u n i t y to s u r p a s s t h e s e o u t c o m e s w i t h a r t h r o s c o p i c t e c h n i q u e s c e r t a i n l y exists. 32 F o r t h o s e w h o w i s h to p u r s u e t h a t e n d , I r e c o m m e n d t h a t c a r e f u l p a t i e n t s e l e c t i o n c r i t e r i a b e f o l l o w e d as o u t l i n e d i n t h i s article. O n e m u s t r e c o g n i z e i n t r a o p e r a t i v e l y w h e n t h e arthroscopic technique will produce inadequate ligament h e a l i n g a n d a b a n d o n it i n f a v o r of m i n i - o p e n a n c h o r placement or full-open traditional repair.

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TREATMENT OF ACUTE SCAPHOLUNATE AND LUNOTRIQUETRALLIGAMENT INJURIES

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