Treatment of scapholunate dissociation: ligamentous repair associated with modified dorsal capsulodesis

Surgical repair of posttraumatic injuries of the scapholunate ligament: A literature study

Background and research aims

Scapholunate interosseous ligament rupture can cause wrist issues like pain, strength loss, and cartilage degeneration. While various surgical treatments exist, it's unclear which method is optimal. This study aims to determine the superior treatment approach for scapholunate dissociation.

Methods

In Pubmed, Embase, Scopus and Web of Science was searched for articles reporting results of surgical repair of scapholunate dissociation. Additional inclusion criteria were English- and Dutch-language articles published between January 2000 and December 2022 with at least 8 patients and at least 1 year of follow-up.

Results

Seventeen articles were included, 9 covered tenodesis repair, 2 focused on capsulodesis, 3 on direct scapholunate ligament repair using bone anchors, and 3 on a combination of tenodesis and capsulodesis. No difference could be found between the types of surgical techniques in wrist mobility and grip strength. The Disability of Arm, Shoulder, and Hand score, Visual Analogue Scale for pain and Mayo wrist scores showed no clinically relevant difference. With all methods, normal radiological values were obtained after surgery. The mean scapholunate angle was less than 60° and the scapholunate gap less than 3 mm. However, at longer follow-up an increase in this angle and gap was seen again.

Discussion

This review did not allow to conclude that one technique was better than another to treat scapholunate dissociation because of poor quality of the included studies. Pre- and postoperative values were not always reported, there were insufficient comparative studies, and randomized prospective studies were missing.

Histological characterization of the human scapholunate ligament

The scapholunate interosseous ligament (SLIL) plays a fundamental role in stabilizing the wrist bones, and its disruption is a frequent cause of wrist arthrosis and disfunction. Traditionally, this structure is considered to be a variety of fibrocartilaginous tissue and consists of three regions: dorsal, membranous and palmar. Despite its functional relevance, the exact composition of the human SLIL is not well understood. In the present work, we have analyzed the human SLIL and control tissues from the human hand using an array of histological, histochemical and immunohistochemical methods to characterize each region of this structure. Results reveal that the SLIL is heterogeneous, and each region can be subdivided in two zones that are histologically different to the other zones. Analysis of collagen and elastic fibers, and several proteoglycans, glycoproteins and glycosaminoglycans confirmed that the different regions can be subdivided in two zones that have their own structure and composition. In general, all parts of the SLIL resemble the histological structure of the control articular cartilage, especially the first part of the membranous region (zone M1). Cells showing a chondrocyte-like phenotype as determined by S100 were more abundant in M1, whereas the zone containing more CD73-positive stem cells was D2. These results confirm the heterogeneity of the human SLIL and could contribute to explain why certain zones of this structure are more prone to structural damage and why other zones have specific regeneration potential. RESEARCH HIGHLIGHTS: Application of an array of histological analysis methods allowed us to demonstrate that the human scapholunate ligament is heterogeneous and consists of at least six different regions sharing similarities with the human cartilage, ligament and other anatomical structures.

Arthroscopic scapholunate ligament repair and dorsal capsulodesis with suture anchor in acute and subacute scapholunate dissociation

PURPOSE

The objective of this study was to investigate the potential of arthroscopic scapholunate ligament repair and dorsal capsulodesis with suture anchor as a treatment option for patients experiencing symptomatic acute and subacute (< 3 months) scapholunate instability.

METHODS

From Jan. 2017 to Jan 2020, 19 wrists with acute or subacute tears of the SL ligament with symptomatic instability were treated with arthroscopic SL repair and dorsal capsulodesis with a suture anchor. The average time from injury to operation was 8.8 weeks (range, 4-11 weeks) and the regular follow-up mean duration at our clinic was 26.5 months (range, 24-32 months). The pain score according to the visual analog scale, wrist range of motion, grip strength, radiographic outcomes and functional outcomes according to the Modified Mayo Wrist Score (MMWS) were evaluated preoperatively and postoperatively during the follow-up period.

RESULTS

All 19 patients had rupture and dissociation of the SL ligament in the radiocarpal joint. The total arc of wrist motion in the flexion-extension plane loss averaged 5.1° (P > .01).The Wilcoxon signed-rank test was used to compare the results: grip force improved significantly with 14.7% improvement of that on the normal side (P < .01); the postoperative MMWS was significantly better than the preoperative scores (P < .01). Of 19 patients of the series, 18 patients (94.7%) achieved good or excellent results according to the MMWS and 16 patients (84.2%) resumed their previous activities. Only one patient (5.3%) had residual laxity of the scapholunate ligament joint at 15 months of follow-up.

CONCLUSIONS

At a minimum of two years of follow-up, patients with acute or subacute symptomatic dissociation of scapholunate ligament instability who underwent arthroscopic scapholunate ligament repair and dorsal capsulodesis with suture anchor treatment had satisfactory results.

LEVEL OF EVIDENCE

Level IV, case series.

InternalBrace for Intercarpal Ligament Reconstruction

Scapholunate and lunotriquetral instability are common causes of chronic, debilitating wrist pain and functional impairment. In the setting of subacute or chronic injuries with predynamic or dynamic instability, the ideal surgical approach remains unclear. In January 2020 the authors started enrolling patients with predynamic and dynamic instability in an Institutional Review Board-approved prospective study, aimed at meticulously studying outcomes using the all-dorsal InternalBrace reconstruction technique. The all-dorsal technique described herein is straightforward, efficient, and easy to learn, with early outcomes equivalent or superior to those of other techniques.

Management of Complex Hand and Wrist Ligament Injuries

Ligamentous injuries in the hand and wrist are often underdiagnosed and can present with significant functional limitations if there is untimely recognition of injury. Adequate repair or reconstruction is critical in restoring joint stability and mobility. The purpose of this review is to provide an overview of the metacarpophalangeal joint, scapholunate interosseous ligament (SLIL), and non-SLIL carpal ligament anatomy, diagnosis, imaging, treatment consideration and options, as well as surgical techniques encompassing repair, reconstruction, and fusion.

Current Concepts in Scapholunate Instability Without Arthritic Changes

Scapholunate instability (SLI) is the most common carpal instability described. SLI leads to a degenerative arthritic pattern known as scapholunate advanced collapse (SLAC). Diagnosis of SLI can be challenging in pre-dynamic and dynamic stages. CT arthrogram, MR arthrogram and dynamic fluoroscopy are helpful in diagnosis while arthroscopy remains the gold standard. SLI is a multi-ligament injury, which involves not only the scapholunate interosseous ligament (SLIL) but also the extrinsic carpal ligaments. Hence, it is better described as an injury compromising the 'dorsal scapholunate(dSLL) complex'. A repair can be attempted for acute SLI presenting within 6 weeks of injury. Reconstruction is the mainstay of treatment for chronic SLI without degenerative changes. Multiple repair techniques have been described which include capsulodesis and tenodesis procedures. The clinical outcomes of the techniques have improved over the years. However, a common problem of all these techniques is the lack of long-term data on the outcomes and deteriorating radiological parameters over time. SLI staging is an important factor to be considered in choosing the reconstruction techniques for a better outcome. Currently, there is a trend towards more biological and less invasive techniques. Regardless of the technique, it is important to preserve the nerve supply of the dorsal capsuloligamentous structures of the wrist. Arthroscopic techniques being minimally invasive have the advantage of less collateral damage to the capsuloligamentous structures. Rehabilitation involves a team approach where a protected dart thrower's motion is allowed after a period of immobilization. Strengthening SL-friendly muscles and inhibiting SL-unfriendly muscles is a key principle in rehabilitation.

Long-term Outcomes of Delayed Scapholunate Ligament Repair After Complete Rupture of the Ligament

Treatment of isolated complete tear of the scapholunate ligament is challenging. The purpose of this study was to determine (1) whether delayed repair of only scapholunate ligament is an option without other reconstruction procedures and (2) whether functional outcomes are possible despite radiographic presence of arthritis. This study included patients who had complete ligament tear at exploration and underwent only scapholunate ligament repair without capsulodesis or tenodesis. Fifteen patients returned for clinical and radiographic examinations. Preoperatively, mean scapholunate gap was 2.9 mm and 4.58 mm on posteroanterior and tangential posteroanterior views, respectively. Postoperatively, the final mean gap was 2.5 mm and 3.9 mm on the posteroanterior and tangential posteroanterior views, respectively. The mean preoperative and final scapholunate angles were 74° and 72.6°, respectively. Seven patients had radiographic arthritis at final follow-up. Delayed scapholunate repair is possible after complete ligament tear. At long-term follow-up, clinical functional outcomes may not correlate with radiographic presence of degenerative arthritis. [Orthopedics. 2021;44(3):e446-e453.].

Arthroscopic Reinsertion of Acute Injuries of the Scapholunate Ligament Technique and Results

Objective  To describe a technique for treating acute injuries of the scapholunate ligament (SLL) by performing an arthroscopic reinsertion of the SLL and dorsal capsulodesis and to present the results obtained. Methods  The study deals with an analytical, prospective clinical study that included 19 consecutive patients with acute injury of the SLL. The range of joint motion, grip strength, pain according to the visual analog scale, functional outcomes according to the Mayo Wrist Score (MWS), and the QuickDASH Score were studied preoperatively and 6 and 12 months postoperatively. The complications and necessary reinterventions were recorded. Results  Nineteen patients with acute injury of the SLL were studied; mean age was 44 ± 2 years, 74% males, 58% complete rupture, and 42% partial rupture, treated with the above-mentioned technique. Thirty-seven percent also had a distal radius fracture and there was one case of perilunate dislocation. Improvement in pain, grip strength, joint balance, and functionality was observed 6 and 12 months postoperatively, with 79% of the cases with good or excellent results Conclusion  The arthroscopic reinsertion and dorsal capsular reinforcement of the SLL, allow a reliable and stable primary repair of the dorsal aspect of the ligament in acute or subacute SL injuries where there is tissue that can potentially be repaired, thus achieving an anatomical repair similar to that obtained with open surgery, but without the complications and stiffness secondary to aggressive interventions on the soft tissues that are inherent to the open dorsal approach.

Current Techniques in Scapholunate Ligament Reconstruction

Scapholunate ligament injuries are common and can lead to a predictable pattern of arthritis (scaphoid lunate advanced collapse wrist) if unrecognized or untreated. This article describes the relevant anatomy, biomechanics, and classification system, and provides an up-to-date literature-based review of treatment options, including acute repair and various reconstruction techniques. It also helps guide surgeons in making decisions regarding a systematic treatment algorithm for these injuries.

Concepts and Artistry in the Treatment of Scapholunate Ligament Injuries

BACKGROUND

Scapholunate ligament injuries are highly challenging injuries to treat. Great uncertainly remains in determining which operative procedures are most effective. Furthermore, there is no consensus on whether surgical intervention changes the natural course of scapholunate injuries.

METHODS

The authors present their assessment of scapholunate injuries and the senior author's preferred surgical techniques. Surgical videos are included. The authors' postoperative management is described.

RESULTS

Operative procedures are selected based on the patient's timing and pattern of injury, degree of associated carpal changes and arthritis, and goals.

CONCLUSION

Over the past 20 years, the senior author has had good success with these techniques, but prospective, longterm outcome studies are needed to critically assess whether these surgical techniques improve patients' long-term function and pain.

Carpal Realignment Using a Strip of Extensor Carpi Radialis Longus Tendon

Scapholunate instability can lead to posttraumatic dysfunction of the wrist. If unrecognized, it commonly leads to degenerative osteoarthritis. Numerous reparative techniques have been proposed with mixed long-term success. We present a technique that uses a distally based strip of the extensor carpi radialis longus to better maintain reduction of the scaphoid and reconstruct the volar and dorsal scapholunate ligament and the scaphotrapezium-trapezoid ligament. To illustrate the technique, we describe a clinical case with 17 months of follow-up.

Changes in Wrist Motion After Simulated Scapholunate Arthrodesis: A Cadaveric Study

PURPOSE

A high incidence of nonunion and relatively poor outcomes with prior fixation techniques has precluded scapholunate (SL) arthrodesis as a standard treatment for SL instability. Our purpose was to determine the impact on range of motion (ROM) of simulated SL arthrodesis via headless screw fixation.

METHODS

We performed baseline wrist ROM for 10 cadaveric wrists using a standardized mounting-and-weights system. Extension, flexion, radial deviation, ulnar deviation, dart-thrower's extension, and dart-thrower's flexion were assessed. Two 3.0-mm headless compression screws were inserted across the SL joint to simulate SL arthrodesis. Goniometric measurements and fluoroscopic imaging were repeated to assess ROM differences after simulated SL arthrodesis. We assessed SL angle and gap during testing to ensure there was no significant motion between the scaphoid and lunate, thus confirming stable simulated fusion. Differences in ROM were compared between baseline and simulated SL arthrodesis using paired t tests.

RESULTS

Mean SL angle remained constant between pre- and post-arthrodesis imaging (47° ± 6° vs 46° ± 4°) and did not change during post-arthrodesis ROM testing, indicating a stable simulated fusion. Compared with baseline, SL arthrodesis had a statistically significant reduction in maximum flexion of 6° and 9° based on fluoroscopy and goniometry, respectively, in dart-thrower's extension of 5° and 9° based on fluoroscopy and goniometry, respectively, and in dart-thrower's flexion of 6° for both fluoroscopy and goniometry. No other ROMs after simulated SL arthrodesis were significantly different compared with baseline.

CONCLUSIONS

The effects of simulated SL arthrodesis on radiocarpal and midcarpal motion compare favorably with motion after SL soft tissue repair and other reconstructive techniques that have been previously reported. The statistically significant decreases in wrist flexion and dart-thrower's extension-flexion after simulated SL arthrodesis are of questionable clinical importance.

CLINICAL RELEVANCE

These results may support reconsidering SL arthrodesis as a viable treatment option for acute or chronic SL instability with regard to apparent minimal adverse effects on functional wrist ROM.

Open Treatment of Acute Scapholunate Instability

Acute treatment of scapholunate instability is important to prevent future complications of dorsal intercalated segment instability and scapholunate advanced collapse. An understanding of the fundamental normal and abnormal mechanics of this problem is vital. Diagnosis in the acute phase is based on clinical and radiographic findings and treatment focuses on primary scapholunate interosseous ligament repair with a reinforcing dorsal capsulodesis. Suture anchor repair with a modified "double-dorsal" capsulodesis is described. Current data show that open repair is a viable option in the acute setting with most patients demonstrating good to excellent functional, clinical, and radiographic results.

A technique for quantifying wrist motion using four-dimensional computed tomography: approach and validation

Accurate quantification of subtle wrist motion changes resulting from ligament injuries is crucial for diagnosis and prescription of the most effective interventions for preventing progression to osteoarthritis. Current imaging techniques are unable to detect injuries reliably and are static in nature, thereby capturing bone position information rather than motion which is indicative of ligament injury. A recently developed technique, 4D (three dimensions + time) computed tomography (CT) enables three-dimensional volume sequences to be obtained during wrist motion. The next step in successful clinical implementation of the tool is quantification and validation of imaging biomarkers obtained from the four-dimensional computed tomography (4DCT) image sequences. Measures of bone motion and joint proximities are obtained by: segmenting bone volumes in each frame of the dynamic sequence, registering their positions relative to a known static posture, and generating surface polygonal meshes from which minimum distance (proximity) measures can be quantified. Method accuracy was assessed during in vitro simulated wrist movement by comparing a fiducial bead-based determination of bone orientation to a bone-based approach. The reported errors for the 4DCT technique were: 0.00-0.68 deg in rotation; 0.02-0.30 mm in translation. Results are on the order of the reported accuracy of other image-based kinematic techniques.

[Muscular control of scapholunate instability. An experimental study]

PURPOSE

As long as the neuromuscular stabilizers are intact, a lesion of the scapholunate ligament may or may not progress to a carpal instability. The mechanisms by which the muscles compensate this defect are not very well known. We designed an experimental study with the aim of clarifying these mechanisms.

MATERIAL AND METHOD

Using 10 fresh wrists, with no pre-existing lesions, we studied the movements of the scaphoid, triquetrum and capitate produced by the isometrical loading of the muscles which move the wrist, each of them isolated or combined, before and after cutting off the scapholunate ligaments. To do this, we placed sensors in each of these bones and used the Fastrack system to record these movements.

RESULTS

The simultaneous loading of the muscles of the wrist produce rotational movements in flexion and supination of the proximal carpal row. After cutting off the scapholunate ligaments, the scaphoid rotates in pronation and flexion, while the triquetrum rotates in pronation and extension. In this situation of a scapholunate lesion, the muscles that worsen the carpal dexasation are the extensor carpi ulnaris and flexor carpi ulnaris. On the other hand, the isolated loading of the radial muscles reduce the scapholunate diastasis, thus improving the carpal alignment.

CONCLUSION

In dynamic scapholunate instabilities, isometric contraction of the ulnar carpal muscles must be avoided, as it promotes the scapholunate diastasis. The rest of the muscles have the opposite effect, stabilizing the carpus when primary stabilizers have failed.

Scapholunate ligament injuries: a review of current concepts

Injuries to the scapholunate ligament are common, especially among young active individuals. Surgeons are faced with a difficult problem because of imperfect surgical outcomes and the high demands of this patient population. Here, we review the current concepts and newest literature on scapholunate ligament injuries as well as the classification and treatment options for each stage of scapholunate instability. Emphasis is on stages in which reconstructive rather than salvage procedures can be performed. The natural history is poorly understood; it is unknown which and how many scapholunate injuries lead to wrist arthritis (SLAC wrist). Partial injuries are rare and in small studies did well with arthroscopic treatment. Complete injuries are graded based on the acuity of the injury, the presence and reducibility of scapholunate malalignment, and, finally, cartilage status. In acute injuries, anatomic repair usually leads to satisfactory results, and many authors augment the repair with a capsulodesis technique. In chronic injuries, the presence of static malalignment usually leads to inferior outcomes. Various techniques have been devised and improved over the years. These techniques appear to provide a more anatomic reconstruction, with less loss of motion; motion is 60-80 % of the contralateral side and grip strength averages 65-90 %. Once there is cartilage loss, the surgeon only has salvage procedures to choose from, tailored to the degree of arthritis.

Long-term results of dorsal intercarpal ligament capsulodesis for the treatment of chronic scapholunate instability

The purpose of this study was to assess the clinical and radiological outcomes of dorsal intercarpal ligament capsulodesis for the treatment of static scapholunate instability at a minimum follow-up of four years. A total of 59 patients who underwent capsulodesis for this condition were included in a retrospective analysis after a mean of 8.25 years (4.3 to 12). A total of eight patients underwent a salvage procedure at a mean of 2.33 years (0.67 to 7.6) and were excluded. The mean range of extension/flexion was 88° (15° to 135°) and of ulnar/radial deviation was 38° (0° to 75°) at final follow-up. The mean Disabilities of the Arm Shoulder and Hand (DASH) score and Mayo wrist scores were 28 (0 to 85) and 61 (0 to 90), respectively. After significant improvement immediately post-operatively (p < 0.001 and p = 0.001, respectively), the mean scapholunate and radiolunate angles deteriorated to 70° (40° to 90°) and 8° (-15° to 25°), respectively, at final follow-up, which were not significantly different from their pre-operative values (p = 0.6 and p = 0.4, respectively). The mean carpal height index decreased significantly from 1.53 (1.38 to 1.65) to 1.48 (1.29 to 1.65) indicating progressive carpal collapse (p < 0.001); 40 patients (78%) had radiological evidence of degenerative arthritis.

Capsulodesis did not maintain carpal reduction over time. Although the consequent ongoing scapholunate instability resulted in early arthritic degeneration, most patients had acceptable long-term function of the wrist.

Comparison of radiographic stress views for scapholunate dynamic instability in a cadaver model

PURPOSE

Many different stress views for the diagnosis of scapholunate (SL) instability have been described in the literature. The purpose of this study is to compare these stress views and determine which view has the greatest utility for demonstrating SL gap radiographically.

METHODS

We performed a literature search for articles describing SL radiographic stress views. We created SL instability in 9 cadaveric wrists by ligamentous sectioning and imaged each specimen using all radiographic views found in the literature. These included the "clenched pencil" view, clenched fist views in varying positions, and traction views. Scapholunate gaps were measured using digital calipers.

RESULTS

We found 8 different SL radiographic stress views specifically described in the literature. In order to further characterize the best stress views, we studied additional parameters, including varied ulnar deviation and degree of obliquity. The clenched pencil view resulted in the most consistent views with the widest SL gaps. With clenched fist views, SL gap trended to a peak at 30° of ulnar deviation.

CONCLUSIONS

The clenched pencil view was the best stress view to demonstrate dynamic SL instability. It also allows for a contralateral comparison on 1 radiograph. We recommend this view when evaluating for SL pathology.

CLINICAL RELEVANCE

This assessment of relative diagnostic utility might assist clinicians in the creation and use of protocols for the diagnosis of dynamic SL instability.

Intercarpal ligamentous laxity in cadaveric wrists

The purposes of this study were to define the range of laxity of the interosseous ligaments in cadaveric wrists and to determine whether this correlated with age, the morphology of the lunate, the scapholunate (SL) gap or the SL angle. We evaluated 83 fresh-frozen cadaveric wrists and recorded the SL gap and SL angle. Standard arthroscopy of the wrist was then performed and the grades of laxity of the scapholunate interosseous ligament (SLIL) and the lunotriquetral interosseous ligament (LTIL) and the morphology of the lunate were recorded. Arthroscopic evaluation of the SLIL revealed four (5%) grade I specimens, 28 (34%) grade II, 40 (48%) grade III and 11 (13%) grade IV. Evaluation of the LTIL showed 17 (20%) grade I specimens, 40 (48%) grade II, 28 (30%) grade III and one (1%) grade IV. On both bivariate and multivariate analysis, the grade of both the SLIL and LTIL increased with age, but decreased with female gender. The grades of SLIL or LTIL did not correlate with the morphology of the lunate, the SL gap or the SL angle. The physiological range of laxity at the SL and lunotriquetral joints is wider than originally described. The intercarpal ligaments demonstrate an age-related progression of laxity of the SL and lunotriquetral joints. There is no correlation between the grades of laxity of the SLIL or LTIL and the morphology of the lunate, the SL gap or the SL grade. Based on our results, we believe that the Geissler classification has a role in describing intercarpal laxity, but if used alone it cannot adequately diagnose pathological instability. We suggest a modified classification with a mechanism that may distinguish physiological laxity from pathological instability.

Radiographic evaluation of the modified Brunelli technique versus the Blatt capsulodesis for scapholunate dissociation in a cadaver model

PURPOSE

A variety of soft tissue surgical procedures have been developed for treatment of scapholunate (SL) dissociation. The purpose of this study was to compare the degree of correction obtained (as measured on preoperative and postoperative radiographs) when performing the modified Brunelli technique (MBT) with that of the more commonly performed Blatt capsulodesis (BC) and to evaluate each technique after simulated wrist motion.

METHODS

Five cadaver wrists were used for this study. The SL interval, SL angle, and radiolunate angle were recorded radiographically, with the SL ligament intact, for each wrist in several loaded positions: neutral, flexion, extension, radial deviation, ulnar deviation, and clenched fist. The SL interosseous ligament was then completely incised, and the radiographic measurements were repeated to demonstrate SL instability. The radiographic measurements were then repeated after MBT reconstruction and after BC reconstruction. Additional radiographic measurements were taken after simulated wrist motion.

RESULTS

Sectioning of the SL ligament resulted in radiographic evidence of SL dissociation. Use of the MBT demonstrated improved correction of the SL interval and the SL angle in the clenched fist position, which was statistically significant when compared with BC. The correction for the SL angle was maintained on the MBT specimens with simulated wrist motion.

CONCLUSIONS

The results demonstrate that in this cadaver model, the MBT better restores the normal carpal relationship of the SL interval and SL angle when compared to the BC, as measured on radiographs. This correction might correlate with improved carpal dynamics and improved clinical outcomes.

[Dorsal capsulodesis for the treatment of scapholunate instability]

OBJECTIVE

To regain stability of the proximal carpal row after scapholunate ligament rupture in order to avoid osteoarthritis and carpal collapse.

INDICATIONS

As additional therapy in scapholunate ligament repair especially in patients with static, but reducible scapholunate malalignment.

CONTRAINDICATIONS

Fixed scapholunate malalignment. Osteoarthritis of the radiocarpal or the midcarpal joint.

SURGICAL TECHNIQUE

Dorsal approach to the carpal joint with release of the second, third and fourth extensor compartment and resection of the dorsal interosseous nerve. Opening of the radiocarpal joint for inspection of the chondral surfaces and the scapholunate ligament for possible repair. If needed, reduction of scaphoid and lunate. Repair of the scapholunate ligament. If a reduction of scaphoid and lunate is necessary, temporary Kirschner wire fixation of the scaphoid to the capitate and the lunate. The dorsal intercarpal ligament is identified and its middle third is dissected and elevated from the triquetrum remaining attached to the distal scaphoid pole. The ulnar end of the elevated part of the dorsal intercarpal ligament is pulled through a split in the dorsal radiotriquetral ligament and fixed to itself. Closure of the proximal and distal third of the dorsal intercarpal ligament.

POSTOPERATIVE MANAGEMENT

Management Immobilization in a below-elbow cast including the metacarpophalangeal joint of the thumb for 6 weeks. Removal of the Kirschner wires, if used, 8 weeks postoperatively. Physiotherapy to improve wrist motion.

RESULTS

Most of the reports in the literature show an improvement of pain. The effect on radiologic parameters and the development of osteoarthritis remains uncertain.

Dorsal intercarpal ligament capsulodesis for predynamic and dynamic scapholunate instability

We treated a prospective series of 18 patients (nine men and nine women) with a mean age of 35 years (range 15 to 57), with chronic predynamic or dynamic scapholunate instability by a dorsal intercarpal ligament capsulodesis using the modified Mayo technique. All the patients were assessed by the modified Mayo wrist score and DASH questionnaire. Wrist arthroscopy was done in all patients before open surgery in order to grade the scapholunate instability and correlate the findings with the radiographic and MRI results. At an average follow-up of 45 months (range 34 to 60) pain significantly diminished (P < 0.05) with improvement in the grip strength (P < 0.005) in all 18 cases. Wrist motion remained almost the same. The mean Mayo wrist score improved from 62 to 84 (P < 0.005).We recommend dorsal capsulodesis by using the dorsal intercarpal ligament flap for the treatment of scapholunate dissociation, when the ligament is still repairable.

Bone-tissue-bone repairs for scapholunate dissociation

Scapholunate dissociation is a commonly seen and treated form of carpal instability. Several surgical options have been used for the repair of scapholunate instability over the past 50 years. These have included benign neglect, reduction and percutaneous pinning, primary repair, partial fusions, tendon weaves, and combinations of these. Recent advancements in scapholunate repair and anatomy have been aimed at a more physiologic repair. Composite replacement of the entire scapholunate interval, similar to other tendon repairs seen in orthopedic surgery, has become popular. Bone-tissue-bone (BTB) autograft replacement from the foot has been used but the problems of a secondary surgical site have resulted in other graft site selections. Currently more commonly used grafts are bone-retinaculum-bone, third or second metacarpal-carpal bone, or hamate-capitate grafts, all performed with or without screw augmentation. Vascularized autograft replacement on pedicled grafts from the hand is being explored. This review discusses the surgeons' indications and technical details of the surgery. The lack of long-term outcome measurements for these BTB surgeries makes it difficult for the hand surgeon to determine the appropriate use of these treatment modalities, but early reports have indicated that the BTB graft will be an important part of scapholunate dissociation treatment.

Scaphotrapeziotrapezoid arthrodesis for arthritis

The main indications for scaphotrapeziotrapezoid (STT) fusion are STT arthritis, rotary subluxation of the scaphoid, and Kienbock disease. The results of this procedure in the literature for each indication are discussed, as are the advantages, disadvantages,and alternative procedures. This article discusses the authors' surgical technique and results. The authors believe this procedure is a viable one in specific clinical scenarios.