Dynamic repair of scapholunate dissociation with dorsal extensor carpi radialis longus tenodesis

Immunohistochemical Investigation of Mechanoreceptors Within the Injured Scapholunate Ligament

PURPOSE

Scapholunate ligaments (SLLs) play a well-established role in maintaining carpal alignment and kinematics, and are innervated with sensory mechanoreceptors located within the ligaments. They are involved in the afferent arc of dynamic wrist stability. The aim of this study was to describe the changes in these mechanoreceptor populations in injured SLLs.

METHODS

Injured SLLs were collected from human wrists at the time of SLL reconstruction or limited wrist fusion, where the ligament remnants would otherwise be discarded. These specimens were formalin-fixed and paraffin-embedded for immunohistochemical analysis to identify mechanoreceptors, which were then classified by type and location within the ligament.

RESULTS

A total of 15 ligaments were collected, with the interval from injury ranging from 39 days-20 years. Eleven ligaments were collected less than one year after injury, and four ligaments were collected two years or more after injury. A total of 66 mechanoreceptors were identified, with 50 mechanoreceptors identified in nine of the 11 specimens collected less than one year after injury. In this group, 54% of the mechanoreceptors resided in the volar subunit, 20% in the dorsal subunit, and 26% in the proximal subunit. Two of the four specimens collected two years or later after injury contained mechanoreceptors, all of which were located in the dorsal subunit. Increasing time from injury demonstrated a decline in mechanoreceptor numbers within the volar subunit.

CONCLUSIONS

Mechanoreceptors were consistently located in the SLL, particularly in the volar subunit of specimens collected less than one year after injury.

CLINICAL RELEVANCE

Ligament reconstruction techniques aim to primarily reconstitute the biomechanical function of the disrupted SLL; however, re-establishing the afferent proprioceptive capacity of the SLL may be a secondary objective. This suggests the need to consider the reconstruction of its volar subunit particularly in those managed within one year of injury.

Long-term Results of the Treatment of Scapholunate Instability with Dynamic Extensor Carpi Radialis Brevis Tenodesis

Scapholunate dissociation is the most common form of carpal instability. This retrospective case series aimed to assess long-term results obtained by treating scapholunate instability with dynamic tenodesis using the entire extensor carpi radialis brevis tendon, which is detached from the base of the third metacarpal, rerouted in the third extensor compartment, and fixed at the distal portion of the scaphoid to maintain reduced rotatory subluxation.

Methods

Nine patients with scapholunate instability were treated. We reviewed eight patients with a mean follow-up of 12 years. One subgroup of four patients was affected by static scapholunate instability, and the other by dynamic scapholunate instability. Disability of the Arm, Shoulder, and Hand score, Patient Rated Wrist Evaluation score, modified Mayo score, and radiographs were used to determine functional and anatomical outcomes.

Results

Excellent functional results did not correlate with radiological outcome in patients with static scapholunate instability. In this subgroup, scapholunate angle and gap and radiolunate angle improved in average but remained in the pathologic range. In only one of these patients, osteoarthritis was observed. In the subgroup of patients affected by dynamic instability, very good functional outcomes correlate with radiological results, except in one patient who developed arthritic changes.

Conclusions

Dynamic tethering of the scaphoid with the extensor carpi radialis brevis tendon might be indicated in the treatment not only in patients affected by dynamic scapholunate instability but also in patients with static instability. Prospective studies with a larger number of patients are required to evaluate this method.

Dynadesis for Treatment of Dynamic Scaphoid Instability with 20-Year Results

Background  Even though the scapholunate interosseous ligament is the most common wrist ligament injury, its treatment remains a challenge for hand surgeons. We report on a surgical treatment (Dynadesis) for dynamic scaphoid instability (DSI) with a 20-year follow-up period. Description of Technique  Dynadesis utilizes antagonist forearm muscles in order to synergistically provide dynamic stabilization to the scaphoid when the wrist is loaded. It is a tendon-to-tendon transfer with the following two components: 1) Dorsal-The extensor carpi radialis longus (ECRL) is passed through a hole in the reduced, distal scaphoid, providing the scaphoid with an independent extension force. 2) Volar-A dynamic checkrein is created by tension-locking the ECRL tendon around the flexor carpi radialis (FCR) tendon. The portion of the FCR distal to the scaphoid tethers and tightens with contracture of the ECRL and FCR muscles. Patients and Methods  Twenty patients (21 wrists) were treated with Dynadesis and reevaluated 20 years later (range: 20-27 years). Results  Average grip strength improved by 8 kg. The average wrist flexion-extension arc decreased by 3 ° . Wrist X-rays showed no radiocarpal arthritis. On the Mayo wrist score, 81% reported excellent to good results (average: 89). Pain levels improved by 90%, with 76% of patients reporting no pain. All patients (100%) were satisfied with their results and would recommend the procedure. Conclusions  Dynadesis is specifically designed for the treatment of DSI. It avoids the eventual complication of osteoarthritis and does not sacrifice wrist motion. A predictable and satisfactory long-term result is obtainable with correct patient selection based on clinical staging and arthroscopic findings.

Design Requirements for Scapholunate Interosseous Ligament Reconstruction

Background  As numerous repairs, reconstructions, and replacements have been used following scapholunate interosseous ligament (SLIL) injury, there is a need to define the structural requirements for any reconstruction or replacement. Methods  Research has been conducted on the force needed to keep the scaphoid and lunate reduced following simulated injury, the failure force of the native SLIL and various replacements, the stiffness of the SLIL and replacements, and the torsional resistance of the scaphoid relative to the lunate. Results  Forces on the order of 50 N are needed to keep the scaphoid and lunate reduced during simple wrist motions in the chronically injured wrist. Even greater forces (up to 110 N) are needed to keep the bones reduced during strenuous activities, such as pushups. The failure force of the entire SLIL has been reported to be as high as 350 N and the failure force of just the dorsal component of the SLIL to be 270 N. Conclusions  The design requirements for a reconstruction or repair may vary depending upon the demands of the patient. In a high demand patient, a reconstruction needs to support the above-mentioned forces during cyclic loading (50 N), when performing strenuous activities (110 N), or during a fall (at least 350 N). Any artificial replacement must undergo careful biocompatibility testing.

Suture-button Fixation and Arthroscopic Dorsal Ligamento-capsulodesis in Chronic Scapholunate Dissociation

The treatment choice in scapholunate (SL) injury depends on the extent of the SL ligament tear, chronicity of injury, quality of the ligament remnants, reducibility of carpal malalignment, and cartilage status of the radiocarpal and midcarpal joints. In the absence of degenerative changes with chronic reducible dissociation, the optimal treatment would be the reconstruction of the SL interosseous ligament. Various SL reconstruction techniques via open or arthroscopic approaches have been described over the years; they include tendon reconstructions, volar/dorsal capsulodesis, SL allografts, bone-tissue-bone composite grafts, reduction and association of the scaphoid and lunate procedure, SL axis method, and SL internal brace technique. However, all of these techniques have their own shortcomings and disadvantages. The present study demonstrates a new technique using a suture-button device for the reduction and fixation of SL diastasis. The suture-button system is positioned between the scaphoid and the triquetrum, the direction of the system prevents scaphoid flexion and maintains continuity of the reduction. Arthroscopic dorsal ligamento-capsulodesis technique can be added to achieve biological healing during the stabilization process. The major advantages of this technique over others are a straightforward application with shorter operative time and lack of a need for harvesting a tendon graft. The technique is performed through mini-incisions, which enable a shorter postoperative recovery time and rehabilitation period and a quicker restoration of function which decreases the risk of joint stiffness. Furthermore, large bone tunnels which increase the risk of fracture are avoided.

Management of chronic scapholunate ligament injury

Scapholunate ligament is the most commonly injured ligament in the wrist and requires accurate diagnosis and treatment. It presents with pain, stiffness and can lead to carpal instability as well as degenerative arthritis if left untreated, with subsequent loss of function and disability. There are several management options currently available but there is no consensus on how best to manage a wrist with chronic sequelae of scapholunate ligament injury. This review explores available evidence in the literature on optimal treatment options including non-operative and operative procedures, relevant surgical techniques and their associated outcomes. A summary of the current concepts in the management of Chronic Scapholunate ligament injury is presented.

Extensor Carpi Radialis Longus Tenodesis Using a Biotenodesis Screw for Treatment of Symptomatic Geissler 2 Scapholunate Dissociation

Treatment of scapholunate dissociation (SLD) depends on the degree of injury. We present our technique of extensor carpi radialis longus (ECRL) tenodesis for Geissler grade 2 SLD and our preliminary results. After arthroscopic confirmation of Geissler grade 2 SLD, we use a single incision and a polyetheretherketone (PEEK) anchor, attaching half of the ECRL tendon to the scaphoid. Preliminary results include improvements in QDASH, QDASH (work) and QDASH (sports/music), a median satisfaction level of 4/5 (satisfied), and a low complication rate. Our method is a safe, reproducible, and effective treatment of symptomatic Geissler grade 2 SLD that has failed nonoperative management, with technical advantages over alternative methods in the literature.

Surgical outcomes of chronic isolated scapholunate interosseous ligament injuries: a systematic review of 805 wrists

Background

Management of chronic isolated scapholunate interosseous ligament (SLIL) injuries has generated a substantial volume of low-quality literature with descriptions of multiple new surgical techniques, and the impact of instability pattern and the optimal surgical technique remain unclear. The primary goal of this review was to compare clinical, radiographic and patient-rated outcomes between current surgical techniques.

Methods

We performed a systematic literature search using multiple databases. We analyzed clinical, radiographic and patient-reported outcomes. We used a fixed-effects model weighted by sample size with combined outcomes estimated via least squares means with 95% confidence intervals. We also performed a subgroup analysis of static versus dynamic instability.

Results

We assessed 805 procedures from 37 study groups, with 429 procedures used in subgroup analysis. There were no statistically significant differences in outcomes between surgical techniques or in subgroup analysis. Overall, postoperative wrist flexion and pain scores decreased, and grip strength and patient-rated outcomes improved.

Conclusion

Compared to overall preoperative values, modest improvements in pain score, grip strength and functional outcome scores were obtained from a range of reconstructive procedures performed for chronic isolated SLIL injuries. No significant differences could be ascertained between surgical techniques, potentially owing to the low quality of evidence and procedure heterogeneity. This study provides accurate preoperative reference values for future studies, highlights the controversial clinical impact of instability classification, and the need for higher-quality multicentre or collaborative trials to improve our understanding and management of this common injury.

Treatment of chronic scapholunate dissociation with tenodesis: A systematic review

Scapholunate (SL) instability is the most common dissociative carpal instability condition. It is the most frequent cause of wrist osteoarthritis, defined as scapholunate advanced collapse or SLAC wrist. Familiarity with the SL ligament complex is required to understand the various features of SL instability. Damage to the SL interosseous ligament is the main prerequisite for SL instability; however the extrinsic, palmar and dorsal ligaments of the carpus also come into play. When more than 6 weeks has passed since the initial injury event, SL instability is considered chronic because ligament healing is no longer possible. Before osteoarthritis sets in and when the SL instability is still reducible (scaphoid can be reverticalized), ligament reconstruction surgery is indicated. Since the end of the 1970s, various ligament reconstruction or tenodesis techniques have been described. These techniques are used in cases of chronic, dynamic or static reducible SL instability, when no repairable ligament stump and no chondral lesions are present. The aim is to correct the SL instability using a free or pedicled tendon graft to reduce pain while limiting the loss of mobility and protecting against osteoarthritis-related collapse in the long-term. We will perform a systematic review of the various tenodesis techniques available in the literature.

Update on operative treatment of scapholunate (SL) instability for radiologists: part 1-SL ligament repair, dorsal capsulodesis and SL ligament reconstruction

Scapholunate instability is the most common form of carpal instability. Imaging (especially radiography) plays an important role in the staging, management and post-operative follow-up of scapholunate (SL) instability. The goals of this article are to review the pre-operative staging of SL instability, the surgical options for repair and reconstruction of the SL ligament, along with the normal postoperative imaging findings as well as complications associated with these surgical options.

Carpal Ligaments: A Functional Classification

Recent laboratory research has disclosed that carpal ligaments exhibit different kinetic behaviors depending on the direction and point of application of the forces being applied to the wrist. The so-called helical antipronation ligaments are mostly active when the wrist is axially loaded, whereas the helical antisupination ligaments constrain supination torques to the distal row. This novel way of interpreting the function of the carpal ligaments may help in developing better strategies to treat carpal instabilities.

Combined Tenodesis-Capsulodesis for Scapholunate Instability: Minimum 2-Year Follow-Up

Background The aim of this study is to evaluate the clinical and radiological midterm results of a combined dorsal tenodesis-capsulodesis for static and reducible scapholunate dissociation (SLD). Patients and Methods We evaluated 20 of 22 consecutive patients with static SLD minimum with follow-up of 2 years operated between 2003 and 2012. The mean age was 40 years (range: 23-65 years). Seventeen were men. Final evaluation included comparative wrist range of motion (ROM) and grip strength, pre- and postoperative pain and function by visual analog scale, and QuickDASH and Wrightington scores. Radiographs included preoperative, early postoperative, and final X-rays. Scapholunate space (SLS) and scapholunate and radioscaphoid angles (SLA and RSA) were measured. Statistical significance was evaluated with Student t-test, considered significant when p < 0.05. Results Mean follow-up was 67 months (range: 24-126 months). Mean final ROM was: flexion 55 degrees (73%), extension 62 degrees (90%), radial deviation 19 degrees (82%), and ulnar deviation 44 degrees (90%). Mean grip strength was 44 kg (92%). Pain at rest improved from 3.4 to 0.5 (p < 0.05). Pain in activity improved from 7 to 1.7 (p < 0.05). Final function was 8.5 (preoperative, 5.2; p < 0.05). Mean QuickDASH score improved from 38 to 8 (p < 0.05). Functional Wrightington score was as follows: 13 excellent, 3 good, 1 regular, and 3 poor. There were three postoperative minor complications. Radiological results (preoperative/early postoperative/final follow-up) were as follows: SLS, 4.7/1.6/1.8 mm; and SLA, 60/50/62 degrees; RSA, 39/45/37 degrees. Four patients showed arthritic changes (two SLAC wrist). Conclusion The clinical and radiological results with more than 2-year follow-up suggest that this technique may be effective, reproducible, and safe for symptomatic static and reducible SLD. Level of Evidence Level IV, case series.

Modified minimally invasive extensor carpi radialis longus tenodesis for scapholunate dissociation: a prospective observational study

BACKGROUND

Scapholunate dissociation is the most common form of carpal instability. However, there is no gold standard for operative treatment. In this prospective observational study on 54 patients, a modified minimally invasive dynamic extensor carpi radialis longus tenodesis is described, which is characterized by a smaller approach and application of a cannulated screw and washer for tendon fixation.

METHODS

Quick-Disabilities of Arm, Shoulder and Hand (DASH)-questionnaire results, post-operative satisfaction, range of motion and grip strength are analyzed.

RESULTS

A median Quick-DASH of 54.6 was observed pre-operatively which significantly improved to a median of 28.4 after the procedure (p < 0.001). Median follow-up was 24 months. Of 46 completely followed-up patients, 31 patients (67.4%) reported that they were satisfied with the outcome. Thirty-seven patients (80.4%) would recommend the procedure to a friend. Thirty-five patients (76.1%) reported some kind of complaint in the operated hand during follow-up. There was no association of severity of symptoms and co-morbidities with the outcome. Neither palmar flexion, nor dorsal extension was significantly different between the operated and non-operated wrist. The operated wrists were observed to have less grip strength than non-operated wrists.

CONCLUSIONS

The presented method seems to be as successful as other techniques described in literature. It is less invasive, thus more patient friendly without harming feasibility of future salvage options. However, post-operative complaint rate was quite high.

Biomechanical Evaluation of Scaphoid and Lunate Kinematics Following Selective Sectioning of Portions of the Scapholunate Interosseous Ligament

PURPOSE

To determine the relative roles of the dorsal and volar portions of the scapholunate interosseous ligament (SLIL) in the stability of the scaphoid and lunate.

METHODS

Sixteen fresh cadaver wrists were moved through physiological motions using a wrist joint simulator. Electromagnetic sensors measured the motion of the scaphoid and lunate. Data were collected with the wrist intact, after randomly sectioning the dorsal SLIL first (8 wrists) or the volar SLIL first (8 wrists), and after full ligamentous sectioning. Differences in the percent increase in scaphoid flexion or lunate extension were compared using a t test with significance set at P < .05.

RESULTS

Sectioning the dorsal SLIL accounted for 37%, 72%, and 68% of the increase in scaphoid flexion in wrist flexion-extension, radioulnar deviation, and dart throw motion as compared with complete SLIL sectioning. Sectioning the volar SLIL accounted for only 7%, 6%, and 14%, respectively. In the same 3 motions, sectioning the dorsal SLIL accounted for 55%, 57%, and 58% of the increase in lunate extension, whereas volar SLIL sectioning accounted for 27%, 28%, and 22%.

CONCLUSIONS

The dorsal SLIL provides more stability to the scaphoid and lunate in biomechanical testing. The volar SLIL does provide some, although less, stability.

CLINICAL RELEVANCE

Although this study supports the critical importance of dorsal SLIL repairs or reconstructions, it also shows that there may be some value in implementing a volar SLIL repair or reconstruction.

The role of arthroscopy in carpal instability

Carpal instability is predominantly caused by trauma and presents as a painful wrist with signs and symptoms of weakness, clicking, clunking and a sense of giving way. Wrist arthroscopy is widely regarded as the 'gold standard' in diagnosing and understanding carpal instability. This article is based on an extensive literature search to evaluate the evidence behind the use of wrist arthroscopy in the assessment and management of these patients. There is convincing evidence supporting the role of arthroscopy in diagnosis and assessment of factors involved in the development of carpal instability, but weak evidence for the effectiveness of arthroscopic techniques in the actual treatment of this condition. The article reviews mechanisms behind, and the role for arthroscopy in the management of scapholunate, lunotriquetral, midcarpal and radiocarpal instability. It also presents how the author incorporates the 'evidence-base' into an 'experience-based' clinical practice.

Radiographic evaluation of the modified Brunelli technique versus a scapholunotriquetral transosseous tenodesis technique for scapholunate dissociation

PURPOSE

To compare reduction of the scapholunate articulation using a transosseous tenodesis through the scaphoid, lunate, and triquetrum (SLT) with the modified Brunelli technique (MBT) in a cadaver model, as measured by scapholunate (SL) angle and diastasis on radiographs.

METHODS

Twelve fresh-frozen cadaveric wrists were radiographically examined in a neutral posture, ulnar deviation, and clenched fist position. The SL angle and diastasis were recorded in each position with the SL ligament intact, after sectioning the ligament and secondary restraints, and after reconstruction by either the MBT (6 wrists) or SLT technique (6 wrists). Wrists were cycled through their maximum flexion and extension arc 100 times to simulate wrist motion after ligament sectioning and reconstruction.

RESULTS

After sectioning and cycling, all wrists demonstrated radiographic evidence of SL diastasis. After ligament reconstruction and cycling, there was no statistically significant difference in diastasis in the MBT reconstructions compared with the SLT reconstructions (3.0 vs 2.4 mm). The SLT group demonstrated better maintenance of the restored SL angle than the MBT reconstructions.

CONCLUSIONS

In this cadaveric model, both MBT and SLT reconstructions restored anatomic parameters in the SL joint, with correction of SL diastasis and SL angle. Future studies to assess the clinical outcomes of SLT tenodesis in patients with chronic SL disruptions are important.

CLINICAL RELEVANCE

The SLT tenodesis, with a central biologic tether along the SL axis and dorsal reinforcement, may prove clinically useful.

Assessment of scapholunate instability and review of evidence for management in the absence of arthritis

Scapholunate ligament tear is a common wrist injury and may lead to degenerative arthritis of the wrist in the long term. We review the assessment and classification of scapholunate instability and discuss the findings from our search for evidence for the management of scapholunate instability in the absence of arthritis. Strong evidence (level 1 or 2) for management is lacking and published recommendations are largely experience-based. The choice of procedure in the absence of arthritis depends on the extent of the tear, quality of the ligament remnants, and reducibility of the joint. Prospective, randomized studies with validated outcome measures are needed to establish the efficacy of intervention on symptoms and function and its effect on the risk of future arthritis.

The role of three-ligament tenodesis in the treatment of chronic scapholunate instability

Restoring ligamentous control in dissociative carpal instability is a major issue in protecting against osteoarthritis. We present clinical and radiological results for 20 patients who underwent flexor carpi radialis three-ligament tenodesis and were prospectively reviewed at a mean follow-up of 25.1 months. Three-ligament tenodesis significantly relieved pain and increased grip strength, wrist function at the expense of joint stiffness. This improvement was not seen in cases of dynamic instability. However, ligamentous loosening did result in rapid recurrence of radiological anomalies and frequent complications. This study challenges the long-term benefit of three-ligament tenodesis in both dynamic and static chronic scapholunate instability.

The role of MDCT arthrography in the follow-up of scapholunate stabilisation

PURPOSE

The aim of this study was to assess outcomes in a group of patients with scapholunate dissociation treated with stabilisation surgery (Brunelli-Stanley) and to compare arthrography with multidetector computed tomography (MDCT) with conventional radiography, the gold standard in the follow-up of wrist surgery.

MATERIALS AND METHODS

Twelve patients (13 wrists) underwent surgery for scapholunate dissociation and were followed up with clinical (visual analogue scale, Mayo Wrist Score, Patient-Rated Wrist Evaluation, and Disabilities of the Arm, Shoulder, and Hand) and radiological assessment (conventional radiography and CT arthrography). Conventional radiography was assessed for: the scapholunate gap, scapholunate angle, radiolunate angle, capitate-lunate angle, and carpal height index; the CT arthrography images were also evaluated for: the distance between the dorsal exit hole of the bone tunnel and the proximal scaphoid pole, the thickness and tension of the flexor carpi radialis (FCR) strip, and any signs of joint degeneration.

RESULTS

Analysis of the data from conventional radiography and MDCT arthrography demonstrated a significant statistical correlation among the measurements obtained on the radiograms and multiplanar CT reconstructions and the patients' clinical outcome.

CONCLUSIONS

Our results show that MDCT arthrography has the same value as conventional radiography in the evaluation of standard parameters (scapholunate gap, scapholunate angle, radiolunate angle, capitolunate angle, carpal height index), but in addition provides an accurate delineation of the FCR tendon graft, allowing differentiation of its thickness, direction and degree of tension.

Arthroscopic dorsal capsulo-ligamentous repair in the treatment of chronic scapho-lunate ligament tears

Introduction Scapholunate ligament injuries usually result due to a fall on the outstretched hand leading to scapholunate instability. The natural history of untreated scapholunate instability remains controversial and usually results in late arthritic changes- the so-called "SLAC" wrist. The advent of wrist arthroscopy helps in early diagnosis and treatment of these serious injuries. In selected cases with reducible scapholunate instability (Garcia-Elias stages 2, 3 and 4) we propose a new "all arthroscopic dorsal capsulo- ligamentous repair" with the added advantage of early rehabilitation and prevention of post-operative stiffness. Material and Methods We report the results of our series of 57 consecutive patients suffering from chronic wrist pain refractory to conservative measures. All patients underwent a thorough clinical examination in addition to a standard set of radiographs and MRI exam; and they were treated by an all-arthroscopic dorsal capsulo-ligamentous repair under loco-regional anesthesia on an ambulatory basis. All patients were available for follow-up at regular intervals during the post-operative period. At follow-up, the wrist ROM in all directions, the grip strength, DASH questionnaire and pain relief based on the VAS were recorded for both- the operated and contra-lateral sides. Results There were 34 males & 23 females with a mean age of 38.72 ± 11.33 years (range 17-63 years). The dominant side was involved in 52 cases. The mean time since injury was 9.42 ± 6.33 months (range 3-24 months) and the mean follow-up was 30.74 ± 7.05 months (range 18-43 months). The mean range of motion improved in all directions. The mean difference between the post- and pre-operative extension was 14.03° (SEM = 1.27°; p < 0.001); while the mean difference between the post-and pre-operative flexion was 11.14° (SEM = 1.3°; p < 0.0001) with flexion and radial deviation reaching 84.3% and 95.72% respectively of the unaffected wrist. The mean difference for the VAS score was -5.46 (SEM = 0.19; p < 0.0001). The mean post-operative grip strength of the affected side was 38.42 ± 10.27 kg (range 20-60 kg) as compared with mean pre-operative grip strength of 24.07 ± 10.51 kg (range 8-40 kg) (p < 0.0001). The mean post-operative grip strength of the operated side was 93.4% of the unaffected side. The DISI was corrected in all cases on post-operative radiographs. The mean difference between the post-and pre-operative SL angles was -8.95° (SEM = 1.28°; p < 0.0001). The mean post-operative DASH score was 8.3 ± 7.82 as compared with mean pre-operative DASH score of 46.04 ± 16.57 (p < 0.0001). There was a negative co-relation between the overall DASH score and the post-operative correction of the DISI deformity with a lower DASH score associated with increasing SL angles. Discussion The dorsal portion of the scapholunate ligament is critical for the stability scapholunate articulation, largely due to its attachment to the dorsal capsule. We have recently conducted a multi-centric anatomical study with international collaboration demonstrating the critical importance of this dorsal scapholunate complex. The all arthroscopic capsulo-ligamentous repair technique provides reliable results in addition to avoiding postoperative stiffness. The overall results at a mean follow-up period of more than 2 years in our series of young, active patients appear to be encouraging.

Scapholunate instability: current concepts in diagnosis and management

Injuries to the scapholunate joint are the most frequent cause of carpal instability and account for a considerable degree of wrist dysfunction, lost time from work, and interference with activities. Although it is insufficient to cause abnormal carpal posture or collapse on static radiographs, an isolated injury to the scapholunate interosseous ligament may be the harbinger of a relentless progression to abnormal joint mechanics, cartilage wear, and degenerative changes. Intervention for scapholunate instability is aimed at arresting the degenerative process by restoring ligament continuity and normalizing carpal kinematics. In this review, we discuss the anatomy, kinematics, and biomechanical properties of the scapholunate articulation and provide a foundation for understanding the spectrum of scapholunate ligament instability. We propose an algorithm for treatment based on the stage of injury and the degree of secondary ligamentous damage and arthritic change.

Arthroscopic dorsal capsuloligamentous repair in chronic scapholunate ligament tears

This article discusses the preliminary results of treatment of chronic scapholunate lesions by arthroscopic dorsal capsuloligamentous repair, which does not require open exposure of the wrist capsule. Thirty six patients underwent arthroscopically assisted dorsal capsuloplasties. Sixteen had percutaneous pinning. Mean follow-up was at 11.4 months. The average arc of motion was 105°preoperatively and 120°postoperatively. The average grip strength attained 92% of the contralateral side. Most of the results were excellent-to-good. Seven professional athletes returned to preinjury level. Arthroscopic dorsal capsuloligamentous repair is a promising option, but a longer follow-up is necessary to confirm these results.

Arthroscopic dorsal capsuloplasty in chronic scapholunate ligament tears: a new procedure; preliminary report

We report our preliminary results of arthroscopic dorsal capsuloplasty for chronic scapholunate lesions to obviate the need for an open exposure of the wrist capsule. Twenty-two consecutive patients with scapholunate ligament tears underwent an arthroscopically-assisted dorsal capsuloplasty with or without percutaneous pinning. The mean age of subjects was 36 years (range, 27 to 55 years). The mean preoperative delay was 9 months (range 3 to 24 months). Criteria for surgery were persistent pain over the dorsal radial wrist in the scapholunate region and a positive finding on performing Watson's test. All patients were reviewed at a mean follow-up of 13 months (range, 7 to 19 months). The range of motion was recovered with a slight limitation in flexion in only four cases. The average grip strength attained was 96% of the contralateral side. The results in terms of pain were excellent. The seven high level athletes resumed practice at the same level as prior to the injury. A longer follow-up is necessary to confirm these encouraging preliminary results.

The role of tenodesis in surgery of the upper limb

This paper describes the presence of tenodesis effects in normal physiology and explores the uses of operative tenodesis in surgery of the upper limb.

Scapholunate stabilization with dynamic extensor carpi radialis longus tendon transfer

Dynamic extensor carpi radialis longus tendon transfer to the distal pole of the scaphoid acts synchronously and synergistically with wrist motion to restore the slider crank mechanism of the scaphoid after scapholunate interosseous ligament (SLIL) injury. The procedure is designed to simulate a hypothetical dorsal radioscaphoid ligament that more closely approximates the normal viscoelastic forces acting on the scaphoid throughout all phases of wrist motion than does the static checkrein effect and motion limitations of capsulodesis or tenodesis. Extensor carpi radialis longus transfer may be independently sufficient to support normal or near-normal scapholunate and midcarpal kinematics and prevent further injury propagation in patients with partial SLIL tears and dynamic scapholunate instability. Extensor carpi radialis longus transfer alone may improve carpal congruity in patients with static scapholunate instability, but SLIL and dorsal lunate ligament repair or reconstruction is essential for favorable durable outcomes. Extensor carpi radialis longus transfer offers a simple and reasonable alternative to capsulodesis or tenodesis to support these ligament repairs or reconstructions, does not require intercarpal fixation, and allows rehabilitation to proceed expeditiously at approximately 1 month after surgery.

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.