Introduction

In recent years, various investigators have highlighted the role of the dorsal radiocarpal ligament (DRCL) in maintaining carpal stability.^1–4 Tears of the DRCL have been linked to the development of both volar and dorsal intercalated segmental instabilities and may be implicated in the development of midcarpal instability.^5–7 The existence of a DRCL tear when combined with a scapholunate interosseous ligament (SLIL) tear connotes a greater degree of carpal instability. This has been acknowledged by some authors, who have advocated an open SLIL repair versus arthroscopic pinning when there is an associated DRCL tear.⁸ An isolated tear of the dorsal radiocarpal ligament can also be a source of chronic wrist pain.⁹

In most series, the DRCL is overlooked during the typical arthroscopic examination of the wrist. It is difficult to visualize a DRCL tear through the standard dorsal wrist arthroscopy portals because the torn edge of the DRCL tends to float up against the arthroscope while viewed through the 3/-,4 portal and 4/-5 portals, which makes both identification and repair of the DRCL tear cumbersome. It can be seen obliquely through the 1/-,2 or 6-U portals, but visualization of the DRCL across the radiocarpal joint may be laborious in a tight or small wrist—especially if synovitis is present. Wrist arthroscopy through a volar radial portal (VR) is the ideal way to assess the dorsal radiocarpal ligament due to the straight line of sight^10–12 (see chapter on arthroscopic portals).

Indications

A classification system for DRCL tears was devised based on the presence or absence of associated carpal pathology (Table 13.1). Each successive stage denotes a longer-standing and/or more severe condition that negatively impacts the prognosis.

Table 13.1 Classification of Dorsal Radiocarpal Ligament Tears

The ligament with the highest Geissler grade determines the stage.

DRCL – dorsal radiocarpal ligament

SLIL – scapholunate interosseous ligament

LTIL – lunotriquetral interosseous ligament

TFCC – triangular fibrocartilage complex

An arthroscopic DRCL repair is indicated for stage I, or isolated DRCL tears due to the favorable outcomes that can be achieved.^9,13,14 Geissler grade I and II SLIL and/or LTIL ligament injuries are still amenable to arthroscopic treatment. DRCL repairs are also indicated in Geissler grade I and II injuries since repair of a secondary stabilizer may augment the coronal plane stability (Table 13.2). Thermal shrinkage of the ST ligaments can theoretically augment sagittal plane stability of the scapholunate joint. This can be accomplished arthroscopically and is currently under investigation, but no data is available to recommend this procedure as yet. Grade III ligament injuries represent a relative gray area. They can be successfully treated with thermal shrinkage and pinning, which should be augmented with a DRCL repair, but if this is combined with instability of the ulnocarpal joint due to a large TFCC tear and/or Geissler III ligament tear there is a high risk of failure following arthroscopic treatment alone. Grade IV ligament injuries are beyond the realm of arthroscopic treatment and require open repair or reconstruction. Due to the frequent association of DRCL tears when there is a TFCC tear, I would also recommend a DRCL repair if the TFCC tear is treated arthroscopically.

Table 13.2 Algorithm for Treatment of DRCL Tears

DRCL – dorsal radiocarpal ligament

SLIL – scapholunate interosseous ligament

LTIL – lunotriquetral interosseous ligament

PRC – proximal row carpectomy

Contraindications

When the treatment of an SLIL tear or dynamic scapholunate instability includes some type of dorsal capsulodesis, the dorsal incision followed by the creation of a dorsal capsular check-rein to restrain palmar flexion of the scaphoid renders any separate treatment of the DRCL tear unfeasible. When the DRCL tear is seen in association with palmar midcarpal instability (MCI), a soft-tissue repair of the dorsal ligaments will not by itself correct the MCI.^15,16

Contraindications to a DRCL repair would also include those that preclude wrist arthroscopy in general, such as any cause of marked swelling that distorts the topographic anatomy, large capsular tears that can lead to extravasation of irrigation fluid, neurovascular compromise, bleeding disorders, or infection. Unfamiliarity with the regional anatomy is a relative contraindication.

Clinical Studies

A retrospective chart review was performed of patients who underwent diagnostic wrist arthroscopy with the use of a volar radial portal.^13,14 This identified 53 patients (56 wrists) over a six-year period. Additional pathology was seen in 24 patients that was not visible from the standard dorsal portals. This included 22 patients with tears of the dorsal radiocarpal ligament. Static wrist radiographs were obtained for all patients. Radiographs included a neutral-rotation posteroanterior view and a lateral view. None of the wrists showed a static carpal instability pattern. Magnetic resonance imaging was performed under the direction of the referring physician in six patients. Preoperative arthrograms were performed as a part of the diagnostic work-up for wrist pain in 20 patients.

None of the DRCL tears in this series was identified with preoperative arthrography or MRI. A preoperative MRI in one patient with a DRCL tear was misinterpreted as representing a dorsal wrist ganglion. There were no specific historical or physical findings that were helpful in making the diagnosis preoperatively, especially in cases of isolated DRCL tears. Specifically, there was no consistent dorsal wrist tenderness over the DRCL. The concomitant wrist pathology was largely responsible for any positive physical findings. The Watson test was positive in cases where there was coexisting scapholunate ligament pathology. Similarly, there was lunotriquetral or ulnar capsule tenderness and/or crepitus in patients with ulnar-sided wrist pathology.

There were 6 men and 16 women. The average patient age was 40 years (range 25 to 62 years). All patients failed a trial of conservative treatment with wrist immobilization, cortisone injections, and work restrictions. The average length of conservative treatment was seven months. The time interval between injury and surgical intervention averaged 25 months (range 8 to 53 months). At the time of arthroscopy, four patients were found to have an isolated DRCL tear that was solely responsible for their wrist pain. The remaining 17 patients had additional ligamentous pathology, summarized in Table 13.3. A dorsal capsulodesis was performed in seven patients as the primary treatment for derangements of the SLIL.

Thirteen of the 21 patients underwent an arthroscopic DRCL ligament repair and/or thermal shrinkage (repair = 5, repair + shrinkage = 6, shrinkage = 2), as described in material following. Ten of these patients underwent ancillary procedures for treatment of the coexisting wrist pathology. Lunotriquetral tears were treated with debridement and pinning. Triangular fibrocartilage tears were debrided or repaired. Scapholunate ligament tears or instability was treated with capsulodesis ± repair. One patient had generalized arthrofibrosis (MG), which precluded a DRCL repair. Concomitant nerve entrapment was a common finding, which was treated at the same time.

The average duration of the follow-up period was 16 months (range 7 to 41 months), with one patient lost to follow-up at four weeks. Pain was graded as none, mild, moderate, and severe.¹⁷ Wrist extension, wrist flexion, radial deviation, ulnar deviation, and grip strength were assessed. Wrist range of motion was compared with presurgical values. Grip strength was compared with the contralateral side at follow-up evaluation.

Patient outcomes are summarized in Table 13.4. The four patients who underwent an isolated DRCL repair were satisfied with the outcome of surgery and would repeat the surgery again because it improved their symptoms. All four patients graded their pain as none or mild. None of these patients were taking pain medications. All returned to their previous occupations without restriction. Their wrist motion was unchanged compared to the preoperative status. Grip strengths were 90 to 130% of the opposite side. The wide variety of ancillary procedures in the remaining patients and the small numbers in each subgroup precluded any statistical analysis of the possible influence of the DRCL repair on wrist motion and grip strengths.

A dorsal capsulodesis was performed as the primary treatment for an SLIL tear or a dynamic scapholunate instability in seven patients instead of a DRCL repair. This remains a popular treatment method for both static and dynamic scapholunate instability. The presence of a DRCL tear did not preclude a good result (none or mild pain) in 3/7 patients. The capsulodesis was ineffective in controlling pain in the remaining four patients, three of whom had additional wrist pathology. This is consistent with other studies, which have demonstrated that although pain is improved it does not completely resolve following a dorsal capsulodesis in the majority of cases.¹⁸

Cadaver studies suggest that dynamic scaphoid instability results from an isolated injury to the SLIL without damage to the dorsal intercarpal and DRCL ligaments.⁴ The author has found the corollary to hold true in that 4/7 patients with dynamic scapholunate instability had a DRCL tear but an intact scapholunate ligament. The diagnosis of dynamic carpal instability in these patients hinged upon the demonstration of the abnormal kinematics and increased motion at the scapholunate joint. This easily allowed insertion of a 3-mm probe between the scaphoid and the lunate when viewed from the midcarpal joint (i.e., Geissler grade III¹⁹), yet there was no apparent scapholunate ligament tear while probing from the radiocarpal joint.

The remaining 10 patients had a DRCL tear in combination with ulnar-sided pathology. One patient (AD) was lost to follow-up. Of these nine patients, six had chronic residual pain (with three of these patients showing arthroscopic evidence of osteoarthritis). Soft-tissue procedures alone were ineffective in controlling their symptoms. There was a trend toward a worse outcome when there was coexisting ulnar-sided carpal pathology, which may reflect more severe or longer-standing carpal instability. This was not invariable, however, because 2/9 patients in this group had only occasional mild pain after treatment. The final patient in this subgroup had an associated palmar midcarpal instability with laxity of the lunotriquetral joint (LT). Although a DRCL repair and lunotriquetral joint pinning improved his symptoms, they did not correct the midcarpal instability (which remained mildly symptomatic).

The volar radial portal has been used in 80 patients since 1998. Excluding distal radius fractures and staging for OA, 64 patients were scoped for the investigation and treatment of wrist pain that was unresponsive to conservative treatment. There were 35/64 patients/wrists with DRCL tears, for an overall incidence of 55%. The marked association of DRCL tears in the presence of ligament and TFCC tears was quite surprising. The average age of the patients with DRCL tears was 41 years (range: 19?62 years). The average duration of wrist pain prior to treatment was 20 months (range 4?60 months). In 5 patients an isolated DRCL tear alone was responsible for chronic dorsal wrist pain. Thirteen patients in this series had an SLIL instability and/or tear: 7/13 (54%) also had a DRCL tear. Of this subgroup 4 had a Geissler I/II grade and 3 had a Geissler III/IV grade. Seven patients had an LTIL instability and/or tear: 2/7 (28%) also had a DRCL tear. Of this subgroup 1 had a Geissler I/II grade and 1 had a Geissler III/IV grade. Two patients had a capitohamate ligament tear: 1 of these patients also had a DRCL tear. There were 7 patients with a solitary TFCC tear: 6/7 (86%) were in association with a DRCL tear. One patient had a chronic ulnar styloid nonunion and a DRCL tear. There was TFCC fraying but no tear or detachment. Two or more lesions were present in 23 patients; DRCL tears were present in 12 patients (52%). Of note was that 62% of the combined lesions that were associated with a DRCL tear also included a TFCC tear. One case involved a 24 year old male with a 6 year old ulnar styloid nonunion. Arthroscopy of the distal radioulnar joint established that the deep fibers of the TFCC were well attached to the fovea hence the patient underwent an ulnar styloid excision along with a DRCL repair.

Clinical Relevance

The true incidence of dorsoradiocarpal ligament tears is not known. It is difficult to detect a DRCL tear with nonoperative methods. It is possible that a number of patients presenting with dorsal wrist pain may be misidentified as having dorsal wrist syndrome²⁰ or an occult dorsal wrist ganglion. DRCL tears are poorly seen through an open approach. Although seven patients who underwent a dorsal capsulodesis for scapholunate instability were found to have a DRCL tear during wrist arthroscopy, none of these tears could be identified through a dorsal capsulotomy. This may be partly because the capsular ligaments are best seen from within the wrist joint, or that the DRCL is divided during the surgical approach for a dorsal capsulodesis.

DRCL tears appear to be part of a spectrum of radial and ulnar-sided carpal instability. It is instructive to consider the wrist as having a number of primary and secondary stabilizers. The SLIL, LTIL, and TFC are the primary stabilizers. The capsular ligaments (including the radioscaphocapitate, radiolunotriquetral, ulnolunate, ulnotriquetral, dorsal radiocarpal, and dorsal intercarpal ligaments) can be thought of as secondary stabilizers. A chronic tear of a primary stabilizer may culminate in the attenuation or tearing of the secondary stabilizer. This is seen in patients with long-standing triquetrolunate dissociation of more than six months duration. Arthroscopy in these cases often reveals fraying of the ulnolunate ligaments and ulnotriquetral ligaments.²¹ In the previously referenced series, there was a frequent association of a DRCL tear with either an SLIL or LTIL/TFC tear.

Injury to the DRCL has been implicated in palmar midcarpal instability (MCI).^5,6,15 Soft-tissue repairs of the dorsal ligaments alone appear to be insufficient to correct this type of carpal instability.^15,16 Goldfarb et al. reported on one patient with palmar MCI in whom a diffuse tear involving the dorsal ligaments was shown on a preoperative MRI. A repair of the dorsal ligaments failed to relieve the patient’s symptoms and a midcarpal fusion was ultimately performed.¹⁷ Palmar MCI was seen in one patient in the author’s series, which did not resolve following LTIL pinning and a DRCL repair.

The cause of wrist pain with isolated capsular ligament tears is not entirely clear. In nondissociative carpal instability the pain is believed to be due to dynamic joint incongruity.²² Chronic impingement of a detached ulnar sling on the triquetrum has been implicated as a cause of wrist pain.²³ It is plausible that tears of the DRCL may cause pain through their deleterious effects on carpal stability or through impingement of the torn edge of the DRCL against the lunate. Repair of an isolated tear of a capsular ligament can alleviate wrist pain. This has been demonstrated with repairs of ulnolunate ligament tears.^24,25 All four of the patients with an isolated DRCL tear also had a favorable response to arthroscopic repair. Slater et al. demonstrated that the dorsal wrist ligaments have a constant blood supply.²⁶ The implication of their work is that tears of the DRCL have the potential to heal. This provides a rationale for arthroscopic repair of a DRCL tear.

Arthroscopic ligament plication for combined LTIL and TFC tears has been previously reported.²⁷ The DRCL repair as described stabilizes the torn edge by plicating it to the dorsal capsule, but it does not necessarily restore the integrity of the ligament per se. Its ameliorating effect on wrist pain may act by forestalling impingement on the lunate or by normalizing carpal kinematics, but there is a lack of biomechanical data to support these theories. Thermal shrinkage was added in some patients in an effort to shorten a voluminous DRCL when sutures alone were ineffective.

Shrinkage by itself was used as a primary treatment modality in only two cases, with mixed results (MRO, YB). It was hence abandoned as a solitary procedure. From the previously cited findings, it is apparent that the results of the DRCL repairs are greatly influenced by and partly determined by the outcomes of treatment for the coexisting wrist pathology. What is not known is how much of a poor outcome is attributable to the coexistence of a DRCL tear. It is evident that any type of soft-tissue procedure is inadequate when there are frank degenerative changes.

Equipment and Implants

Surgical Technique

An inside-out arthroscopic repair technique of the DRCL is performed through a volar radial (VR) wrist arthroscopy portal that allows a direct line of sight with the dorsal radiocarpal ligament (Figure 13.1a). A 2-cm longitudinal incision is made in the proximal wrist crease, exposing the flexor carpi radialis (FCR) tendon sheath. The sheath is divided and the FCR tendon retracted ulnarly. The radiocarpal joint space is identified with a 22-gauge needle and the joint inflated with saline. A blunt trochar and cannula are introduced through the floor of the FCR sheath, which overlies the interligamentous sulcus between the radioscaphocapitate ligament and the long radiolunate ligament.

FIGURE 13.1 Inside-out two-cannula DRCL repair. (A) View of an intact dorsoradiocarpal ligament (DRCL) from the VR portal. The hook probe is in the 3/-,4 portal. (B) Dorsal radiocarpal ligament tear (*). (C) Two-cannula repair technique. (D) Insertion of second suture with meniscal repair needle. (E) Suture exiting dorsally prior to tying.

(From Slutsky, DJ. Arthroscopic repair of dorsal radiocarpal ligament tears. Arthroscopy: The Journal of Arthroscopic and Related Surgery 2002;18(9):E49, with permission.)

A 2.7-mm 30 degree arthroscope is inserted through the cannula. A meniscus repair cannula is then inserted adjacent to the arthroscope. In a small wrist, the capsular intervals on either side of the long radiolunate ligament can be used. While visualizing the DRCL tear through the VR portal, a 2–0 absorbable suture on double-armed straight needles is introduced through the meniscal repair cannula. The needles are passed across the radiocarpal joint through the torn edge of the DRCL, exiting through the floor of the fourth extensor compartment (Figure 13.1b through e). One or two horizontal mattress sutures are inserted in this fashion. A small dorsal incision is made to retrieve the sutures before tying, to ensure there is no extensor tendon entrapment.

An outside-in repair is technically easier and has been used more recently. The repair is performed by spearing the radial side of the DRCL tear with a curved 21-gauge spinal needle placed through the 3/-,4 portal while viewing through the arthroscope, which is inserted in the VR portal. A 2–0 absorbable suture is threaded through the spinal needle and retrieved with a grasper or suture snare inserted through the 4/-,5 portal (Figure 13.2a through f). A curved hemostat is used to pull either end of the suture underneath the extensor tendons, and the knot is tied either at the 3/-,4 or 4/-,5 portal. The repair is augmented with thermal shrinkage if the torn edge of the DRCL is voluminous and still protrudes into the joint after the sutures are tied (Figure 13.2g).

FIGURE 13.2 Outside-in DRCL repair technique. (A) Arthroscopic view of DRCL tear from the VR portal. (B) Drawing of DRCL tear. (C) Insertion of curved spinal needle through edge of DRCL tear. (D) Drawing of outside-in technique using two spinal needles and a suture retriever. (E) Insertion of second spinal needle. (F) Arthroscopic view of suture loop prior to tying. (G) Drawing of completed repair. (H) Repair augmented with thermal shrinkage after suture has been tied.

(Figures A, C, E, F, and H from Slutsky, DJ. Clinical applications of volar portals in wrist arthroscopy. Techniques in Hand and Upper Extremity Surgery 2004;8(4):229-38, with permission. Figures B, D, and G from Slutsky, DJ. Arthroscopic repair of dorsal radiocarpal ligament tears. Arthroscopy: The Journal of Arthroscopic and Related Surgery 2005;21(12):1486e1-86e8, with permission.)

Rehabilitation

Following the repair, the patient is placed in a below-elbow splint with the wrist in neutral rotation. Finger motion and edema control are instituted immediately. At the first postoperative visit, the sutures are removed and the patient is placed in a below-elbow cast for a total immobilization time of six weeks. Wrist motion with use of a removable splint for comfort is instituted after cast removal. Gradual strengthening exercises are added after eight weeks. Dynamic wrist splinting is instituted at 10 weeks if needed.

Summary

DRCL tears are more common than previously suspected. The ideal method of detection at this point remains arthroscopy. The arthroscopist must be diligent in recognizing this condition, but ongoing research into the ideal method of treatment is needed.