Analysis of carpal instability: I. Description of the scheme

Dorsal Scapholunate Ligament Reconstruction by Using Palmaris Longus Tendon Graft in Chronic Static Scapholunate Dissociations: Does It Yield Favorable Radiographic and Functional Results?

Background  Scapholunate (SL) instability is the most common dissociative carpal instability, and the most frequent cause of wrist osteoarthritis (OA), termed as scapholunate advanced collapse (SLAC). The aim of this study was to present the mid-term clinical and radiographic results of dorsal SL ligament reconstruction by utilizing free palmaris longus tendon graft in patients with symptomatic, chronic, static SL dissociation; while assessing the safety and efficacy of this technique, Materials and Methods  In total, 42 patients with a mean age of 44.1 (range 26-53) and mean follow-up duration of 69.4 months (range 60-72) with a diagnosis of chronic, static, and reducible SL instabilities with no chondral damage were enrolled. They all underwent dorsal SL ligament reconstruction with the exam same technique. Results  At the last follow-up, patients' mean preoperative SL gap improved from 4.7 (range 4-6) to 2.1 (range 2-3), as did SLA from 84 degrees (range 67-101 degrees) to 66 degrees (range 49-72 degrees)( p <0.001 for both). Preoperative mean VAS (visual analog score), DASH (Disabilities of the Arm, Shoulder and Hand), Mayo wrist scores and SF-36 scores showed significant improvements in the last follow-up visit ( p <0.001, for all). No major complications were acquired in either of the patients. Conclusion  Dorsal SL ligament reconstruction by using free PL tendon graft was detected to provide successful restoration of the normal carpal alignment together with SL joint stability. This procedure, by significantly reducing pain and improving grip strength was detected to yield significantly improved clinical and functional outcomes, together with high patient satisfaction indicated by improved health-related quality of life (HRQOL) scores. Level of Evidence  IV.

The INCA® implant to treat isolated scaphotrapeziotrapezoid osteoarthritis: Preliminary results at a minimum 2 years' follow-up

We report results with the INCA® distal scaphoid pole resurfacing implant anchored within the scaphoid for isolated scaphotrapeziotrapezoid osteoarthritis. Thirty-five implants in 27 patients (mean age, 69 years) were retrospectively included with a minimum follow-up of 2 years. Outcome criteria were pain (VAS), PROMs (QuickDASH, PRWE and MMWS), wrist motion, pinch and grip strength, and radiographic assessment. The average follow-up was 4.6 years. There was a significant improvement in pain, PROMs, grip and pinch strength. Radial deviation and wrist extension showed slight but significant postoperative decrease (-4° for both). Dorsal intercalated segment instability (DISI) was significantly improved postoperatively (7 cases versus 21 preoperatively). There were 2 cases of implant loosening (6%) within the first 10 months: 1 keel malpositioning and 1 insufficient postoperative immobilization. These findings suggest that the INCA® implant is an effective and reliable medium-term solution for isolated scaphotrapeziotrapezoid osteoarthritis. By restoring scaphoid length and gliding on the trapeziotrapezoid surface, the implant contributes to restoring normal bone alignment of the wrist.

Outcomes of Acute Versus Subacute Scapholunate Ligament Repair

Purpose

This study investigated the long-term outcomes of direct scapholunate ligament (SLL) repairs with or without dorsal capsulodesis performed within 6 weeks (acute repair) of a SLL tear versus 6 to 12 weeks following injury (subacute repair).

Methods

A review of medical records from April 1996 to April 2012 identified 24 patients who underwent SLL repair (12 acute, 12 subacute). Patients returned to the clinic for radiographic examinations of the injured wrist, standardized physical examinations, and validated questionnaires.

Results

The mean follow-up times for the acute and subacute groups were 7.2 and 6.2 years, respectively. At the final examination, patients with acute surgery regained more wrist extension (acute = 55°, subacute = 47°). The total wrist flexion-extension arcs, grip strengths, pinch strengths, and patient-rated outcome scores were found to be similar between groups. The final scapholunate gap, scapholunate angle, and the prevalence of arthritis were also found to be similar between the acute and subacute groups.

Conclusions

Although SLL repair is more commonly recommended for treatment of acute SLL injuries, there were no significant long-term differences between acute and subacute SLL surgeries (repair ± capsulodesis).

Type of study/level of evidence

Prognostic III.

Correlation Between Dynamic 4-Dimensional Computed Tomography Data and Arthroscopic Testing of Scapholunate Instability: A Preliminary Study

PURPOSE

The aim of this study was to test the validity and reliability of the assessments of scapholunate (SL) instability status on 4-dimensional (4D) computed tomography (CT) using wrist arthroscopy as a reference standard.

METHODS

Thirty-three patients (16 men, 17 women; mean age, 48 ± 13 years) with suspected SL instability were evaluated prospectively with 4D-CT and wrist arthroscopy. Based on the arthroscopic testing of SL joint, 2 groups were defined: group 1 (n = 8) consisted of patients who had no, or slight, SL malalignment in the midcarpal space and group 2 (n = 25) consisted of patients who had moderate or severe SL malalignment. Two independent readers, who did not know the arthroscopic findings, used 4D-CT to evaluate the SL gap, lunocapitate angle (LCA), and radioscaphoid angle (mean and range values) during radioulnar deviation.

RESULTS

The interobserver reliability was deemed good or excellent for most of the 4D-CT variables, except for the LCA range (moderate) and SL gap range (poor). For both readers, the SL gap mean, maximum, and minimum values were significantly higher (+67%, +78%, and +39%, respectively) and the LCA mean was significantly lower (-17%) in group 2 than in group 1. The radioscaphoid angle range values were lower (-34%) and the radioscaphoid angle mean values slightly higher (+4%) in group 2, but there was no significant difference between the 2 groups. The SL gap range values were also higher (+86% for R1 and +40% for R2) and the LCA range values also lower (-50% for R1 and -31% for R2) in group 2.

CONCLUSIONS

Quantitative 4D-CT data corresponded well with the arthroscopic dynamic analysis of the SL joint in patients with suspected chronic SL instability.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic II.

Carpal Instability: II. Imaging

Beyond clinical examination, the various forms of carpal instability are assessed with radiologic methods and arthroscopy. For this purpose, the imaging demand for spatial and contrast resolution is particularly high because of the small ligamentous structures involved. The entities of carpal instability are classified into degrees of severity. Early (dynamic) forms of instability can either be indirectly detected with X-ray stress views and cineradiography or by direct visualization of ruptured ligaments in high-resolution magnetic resonance (MR) imaging and MR or computed tomography (CT) arthrography, with the latter the standard of reference in imaging. Advanced (static) forms of carpal instability are sufficiently well detected on radiographs; visualization of early carpal osteoarthritis is superior on CT. To prevent disability of the hand, the radiologist has to provide an early and precise diagnosis. This case-based review highlights the imaging procedures suitable for detection and classification of carpal instability.

Carpal Instability: I. Pathoanatomy

The pathoanatomy of carpal instability is multifactorial and usually complex. A thorough medical history and clinical examination are essential, as well as profound knowledge of the specific instability patterns. The stability of the wrist is ensured by the carpal joint surfaces, by intact intra-articular (particularly the scapholunate interosseous ligament) and intracapsular ligaments, and by crossing extensor and flexor tendons, the latter making the proximal carpal row an "intercalated segment." An important classification feature is the distinction between dissociative and nondissociative forms of carpal instability. Among others, scapholunate dissociation, lunotriquetral dissociation, midcarpal instability, and ulnar translocation are the most common entities. Early forms of instability are considered dynamic. In the natural course, static instability of the wrist and osteoarthritis will develop. This review focuses on the pathoanatomical fundamentals of the various forms of carpal instability.

Four-Dimensional CT Analysis of Dorsal Intercalated Segment Instability in patients with Suspected Scapholunate Instability

Background  In this study we sought to evaluate the contribution of dynamic four-dimensional computed tomography (4DCT) relative to the standard imaging work-up for the identification of the dorsal intercalated segment instability (DISI) in patients with suspected chronic scapholunate instability (SLI). Methods  Forty patients (22 men, 18 women; mean age 46.5 ± 13.1 years) with suspected SLI were evaluated prospectively with radiographs, arthrography, and 4DCT. Based on radiographs and CT arthrography, three groups were defined: positive SLI ( n  = 16), negative SLI ( n  = 19), and questionable SLI ( n  = 5). Two independent readers used 4DCT to evaluate the lunocapitate angle (LCA) (mean, max, coefficient of variation [CV], and range values) during radioulnar deviation. Results  The interobserver variability of the 4DCT variables was deemed excellent (intraclass correlation coefficient = 0.79 to 0.96). Between the three groups, there was no identifiable difference for the LCA _mean . The LCA _max values were lower in the positive SLI group (88 degrees) than the negative SLI group (102 degrees). The positive SLI group had significantly lower LCA _cv (7% vs. 12%, p  = 0.02) and LCA _range (18 vs. 27 degrees, p  = 0.01) values than the negative SLI group. The difference in all the LCA parameters between the positive SLI group and the questionable SLI group was not statistically significant. When comparing the negative SLI and questionable SLI groups, the LCA _cv ( p  = 0.03) and LCA _range ( p  = 0.02) values were also significantly different. The best differentiation between patients with and without SLI was obtained with a LCA _cv and LCA _range threshold values of 9% (specificity of 63% and sensitivity of 62%) and 20 degrees (specificity of 71% and sensitivity of 63%), respectively. Conclusion  In this study, 4DCT appeared as a quantitative and reproducible relevant tool for the evaluation of DISI deformity in cases of SLI, including for patients presenting with questionable initial radiography findings. Level of evidence  This is a Level III study.

The 50 most cited papers in chronic scapholunate reconstruction: a bibliometric analysis

PURPOSE

This study identifies the most impactful papers on scapholunate reconstruction and provides a quantitative assessment of the impact of these papers in order to inform future clinical practice, education, and research of this condition.

METHODS

The Scopus database was used in May 2020 to identify the 50 most cited clinical articles pertaining solely to chronic scapholunate reconstruction. Citation number and density, publication variables, and Altmetric Attention Scores (AASs) were collected and analyzed.

RESULTS

The top 50 articles on chronic scapholunate reconstruction produced 1,868 total citations, with an average of 37.36 ± 39.90 citations per article (range 7-196) and an average citation density of 2.44 ± 2.27. US-based publications (n = 20) and articles published in Journal of Hand Surgery (n = 24) were associated with significantly higher citation number and density (p < 0.01 - p = 0.018). In addition, sample size was positively correlated with citation density (rho = 0.312, p = 0.029). Fourteen articles were associated with an AAS (mean score = 4.07 ± 4.70). There was no significant association between AAS and citation number or density, but AAS did significantly predict citation density (coefficient = 0.378, 95% CI: [0.013-0.741], p = 0.043).

CONCLUSION

Numerous factors, such as journal of publication, location, and sample size, were significantly associated with citation number and/or citation density. Interestingly, AAS was predictive of, but not directly correlated with citation density, suggesting that the impact of scapholunate literature may not be adequately captured with a citation analysis.

Evaluation of Dorsal Scaphoid Displacement Using Posterior Radioscaphoid Angle in Patients With Suspected Scapholunate Instability: A Preliminary Study

PURPOSE

To assess the validity and reliability of the posterior radioscaphoid angle (PRSA), an indicator of dorsal displacement of the scaphoid, in distinguishing wrists with and without chronic scapholunate instability (SLI).

METHODS

We prospectively evaluated 40 patients (22 men and 18 women; mean age, 46 ± 13 years) with suspected SLI with radiographs and computed tomography arthrography. Based on these data, 3 groups were defined: positive SLI (n = 16), negative SLI (n = 19), and questionable SLI (n = 5). An independent reader measured the PRSA on sagittal computed tomography images using the same procedure.

RESULTS

The PRSA median values were significantly lower in the negative SLI group (98°) compared with the positive SLI (110°) and questionable SLI (111°) groups. The difference between the positive SLI and questionable SLI groups was not significant. The best differentiation between patients with and without SLI was obtained with a PRSA threshold value of 103° (specificity of 86% and sensitivity of 79%).

CONCLUSIONS

In this preliminary study, PRSA analysis offers a quantitative tool for the evaluation of dorsal scaphoid displacement in cases of SLI, including for patients presenting with questionable initial radiography findings.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic II.

Modified Viegas dorsal capsuloplasty for chronic partial injury of the scapholunate ligament in young athletes: outcomes at 24 months

The treatment of chronic scapholunate ligament tears in patients with high demand, such as young athletes, is difficult as traditional techniques are associated with some loss of wrist motion and grip strength. This retrospective investigation studied young athletes (≤20 years old) with chronic scapholunate ligament lesions and a minimum follow-up of 24 months, treated with a modified Viegas dorsal capsuloplasty. Twenty-six young athletes (mean age 17 years) were included. A partial scapholunate ligament tear (Geissler III) was seen in 25 patients. At the last follow-up, a significantly different improvement was seen in all measured parameters and all patients could return to their original competitive activity, within 6 months (range 4-12) after surgery.Level of evidence: IV.

Four-corner arthrodesis with a dorsal locking plate: 4-9-year follow-up

We report the outcomes of four-corner arthrodesis for advanced wrist collapse in 50 patients (51 wrists) using a dorsal locking plate. At a mean follow-up of 6 years (range 4-9), pain was significantly reduced and wrist function was significantly improved compared with preoperative status. After four-corner arthrodesis, grip strength was 80% of the contralateral side, and wrist motion averaged 50° flexion-extension and 30° radioulnar deviation. Immobilization time was 5 weeks (4-6) and sick-leave was 3 months (2-5) following surgery. There were seven nonunions (14%) that underwent repeat arthrodesis. Three wrists were later converted to total arthrodesis due to persisting pain. Radiographic dorsal impingement was found in five wrists after four-corner arthrodesis and did not require reoperation. The outcomes appear not remarkably different from those reported using other fixation methods other than an apparent earlier return to activities.Level of evidence: IV.

Assessment of scapholunate instability with dynamic computed tomography

We performed a prospective study to evaluate the values of dynamic four-dimensional computed tomography in assessing suspected chronic scapholunate instability. Forty patients were evaluated with radiographs, arthrography, and four-dimensional computed tomography. On plain radiographs and computed tomography, we found 16 patients with definite scapholunate instability, five with questionable scapholunate instability, and 19 with absence of scapholunate instability. We used four-dimensional computed tomography to evaluate the size of the scapholunate gap during radioulnar deviation. The mean and maximal values of the gap size were lowest in the patients with absence of scapholunate instability and highest in those with definite scapholunate instability. When comparing the scapholunate gap sizes of the patients with absent and questionable scapholunate instability, the range of the gap sizes was significantly higher in the patients with questionable scapholunate instability. We conclude that four-dimensional computed tomography aids assessment of chronic scapholunate instability, which allows the differentiation between patients without and those with definite or questionable scapholunate instability. Level of evidence: II.

Treatment of Carpal Instability and Distal Radioulnar Joint Instability

Carpal instability and distal radioulnar joint instability represent an important set of conditions responsible for pain and disability in the wrist. Either condition can occur as a result of ligamentous failure or loss of articular congruity from fractures or a combination of both. Instability itself is a clinical diagnosis supported by relevant imaging modalities. Carpal and distal radioulnar joint instability needs to be considered according to its stage and severity as well as other factors like etiology and chronicity to determine the optimal treatment option. This article summarizes the conditions most relevant to the practice of a hand surgeon, with emphasis divided equally between assessment and diagnosis, staging, and treatment. The 3 most common carpal instability conditions are outlined in this article together with a review on acute and chronic distal radioulnar joint instability.

Treatment of chronic scapholunate instability: Results with three-ligament tenodesis vs. scapholunate and intercarpal ligamentoplasty

In this retrospective case control/comparison study, we compared the clinical and radiological outcomes in patients with chronic scapholunate dissociation treated with three-ligament tenodesis (3 LT) versus scapholunate and intercarpal ligamentoplasty (SLICL). Twenty patients with a mean age of 43 years were treated with the 3 LT procedure and 26 patients with a mean age of 44 years with the SLICL procedure. All patients had chronic reducible scapholunate dissociation without chondral lesions. The two groups of patients were operated on by senior surgeons, at the same facility, over two different time periods. All patients were evaluated (pain, motion, strength, function, X-rays) with a mean follow-up of 28 months (12-49) in the 3 LT group and 36 months (12-54) in the SLICL group. In the both groups, we found a significant improvement in pain levels, grip strength and functional scores (DASH and PRWE). The SLICL group had significantly less pain and greater grip strength than the 3 LT group. Patients in the SLICL group had a greater improvement in their DASH and PRWE Scores. The mean range of motion in flexion-extension was 82° (102° preoperative) in the 3 LT group and 113° (115° preoperative) in the SLICL group. In the 3 LT, there was no significant improvement in the mean static and dynamic scapholunate gaps (3.6 and 4.8 mm postoperatively versus 3.9 and 4.9 mm preoperatively), or the scapholunate angle (75° versus 72°). In the SLICL group, the mean static and dynamic gaps improved significantly (2.3 and 3.0 mm postoperatively versus 3.2 and 4.6 mm preoperatively), as did the scapholunate angle (62° versus 73°). In the 3 LT group, 4 patients developed osteoarthritis. In conclusion, the SLICL procedure for scapholunate ligament reconstruction led to better clinical and early radiological results than the 3 LT technique.

Outcomes of scapholunate intercarpal ligamentoplasty for chronic scapholunate dissociation: a prospective study in 26 patients

We report the outcomes of scapholunate intercarpal ligamentoplasty in 26 wrists. For 15 wrists with static instability and 11 with dynamic instability, we used a free palmaris longus graft to reconstruct the dorsal part of the scapholunate interosseous ligament and the dorsal intercarpal ligament. These patients were evaluated for pain and active wrist range of motion, grip strength and radiological appearance after a mean follow-up of 36 months (range 12-54) after surgery. Pain score was improved from 4.5 to 1.4 at rest and 6.7 to 1.9 during hand use. The average wrist flexion was 57°, extension 56°. Grip strength was 89% of the contralateral side. The mean scapholunate angle decreased from 76° to 62°, and static scapholunate gap reduced from 3.2 mm to 2.3 mm and the dynamic gap from 4.6 mm to 3.0 mm. Scaphoid subluxation was corrected. We conclude that this procedure led to satisfactory clinical and radiological results in a short- to mid-term follow-up.

LEVEL OF EVIDENCE

II.

Long-Term Functional Results of a Wrist Exercise Program for Patients with Palmar Midcarpal Instability

Background  Patients with palmar midcarpal instability have symptoms of pain, combined with clinical signs of abnormal mobility on stressing the joint, an unpredictable blockade feeling, and a noticeable clunk, in the absence of an underlying trauma. No data are available on the effect of conservative treatment for these patients. Purpose  The purpose of this study was to evaluate the effect and the long-term functional outcomes of a wrist exercise program in patients with palmar midcarpal instability. Patients and Methods  All patients diagnosed with palmar midcarpal instability between 2005 and 2011 were included. Patients completed the Patient-Rated Wrist and Hand Evaluation (PRWHE) and the Short Form-36 health (SF-36) questionnaires, scaled their perceived pain before and after treatment, and indicated the effect of the received treatment. Results  A total of 119 patients diagnosed with palmar midcarpal instability were included. The median follow-up time was 6 years (IQR 4.5-7.0). The median PRWHE score after hand therapy was 35.5 and the median mental component of the SF-36 score was 53.9 and the physical component was 45.2. The median perceived pain reduced from eight to four and the median therapeutic effect of the wrist exercise program was five. Conclusion  Although palmar midcarpal instability remains to be a chronic disease, the effectiveness of our wrist exercise program is promising with acceptable long-term functional results and a good quality of life. Level of Evidence  Level IV, retrospective cohort study.

Radiological evaluation of scapholunate intercarpal ligamentoplasty for chronic scapholunate dissociation in cadavers

We performed a cadaveric study to evaluate radiological performance of a technique for scapholunate intercarpal ligamentoplasty designed for treating reducible scapholunate dissociation. We created scapholunate instability in 12 fresh adult cadaveric forearms by sectioning the dorsal scapholunate interosseous ligament and the dorsal intercarpal ligament. All wrists showed scapholunate diastasis, dorsal intercalated segmental instability and posterior scaphoid subluxation. We performed scapholunate intercarpal ligamentoplasty in six wrists and Garcia-Elias three-ligament tenodesis in another six. Wrists were examined radiographically both after ligament sectioning and after ligamentoplasty to compare static and dynamic scapholunate gaps and scapholunate and capitolunate angles. Improvement was statistically significant in all measurements, reflecting a return to normal values. Posterior scaphoid subluxation was also corrected. There was no significant difference between the two treatment groups. Our findings suggest that ligamentoplasty can restore scapholunate joint stability and normal carpal anatomy.

[Mediocarpal instability of the wrist]

Typical lesions of the carpal ligaments are mostly found after a fall on the wrist in hyperextension or as complex injuries after severe trauma, e. g. after a fall from a significant height, motorcycle accident or as accompanying lesions in multiple trauma. The typical mechanisms, patterns and diagnostic algorithms are well known for the common ligamentous injuries (e.g. scapholunate, lunotriquetral and perilunate); therefore, consistent diagnostic procedures and adequate therapy are increasingly performed after such lesions, e. g. by early ligament repair or by ligament reconstruction through augmentation. Within appropriate operative treatment, accompanying fractures are also treated and instabilities are addressed by transfixation of joints by Kirschner wires. If followed by immobilization with a cast or stable brace, healing can be achieved in most cases; however, more problems occur if ligamentous lesions or instabilities are not clearly due to a trauma mechanism and more the result of laxity or hypermobile situations due to a congenital predisposition. In such cases, wrist pain is often described and misdiagnosed as the result of overload or tenovaginitis.

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.

A Biomechanical Perspective on Distal Radioulnar Joint Instability

Background The purpose of this article was to review the anatomy, kinematics of the distal radioulnar joint (DRUJ), and to discuss definition, classification, and diagnosis of DRUJ instability. Methods A biomechanical perspective on physical examination of DRUJ ballottement test was documented. Physiological dynamic DRUJ translation and differences of the translation following sequential ligament sectioning and changes in different forearm and wrist positions were demonstrated. The clinical significance of each ligament's contribution to joint stability in specific wrist positions was addressed. Conclusion Each ligament stabilizing the DRUJ contributed to joint stability depending on the direction (palmer or dorsal) and different positions of the wrist and forearm. DRUJ ballottement test in each wrist and forearm position may detect tears of specific ligament stabilizing the DRUJ.

The Role of Lunate Morphology on Scapholunate Instability and Fracture Location in Patients Treated for Scaphoid Nonunion

BACKGROUND

To determine the association between lunate morphology and the scapholunate instability using radiographic images, and investigate the association between lunate morphology and scaphoid fracture location.

METHODS

Between January 2003 and December 2011, we retrospectively evaluated the plain radiographs and computed tomography (CT) images of 70 patients who underwent surgical intervention for a scaphoid nonunion, in order to determine the association between lunate type (I or II) and scapholunate instability or scaphoid fracture location. We determined the scaphoid fracture location using the fragment ratio and measured the radiolunate angle and capitate-triquetrum (C-T) distance.

RESULTS

A type II lunate was present in 68.6% (48 of 70 cases). Mean fragment ratio of fracture location was 50.6% in the type II lunate group and 56.2% in the type I lunate group (p = 0.032). Sixteen of the 70 patients had dorsal intercalated segmental instability (DISI) deformities. Nine of 22 cases showed DISI deformity in type I lunate and 7 of 48 cases showed DISI deformity in type II lunate (p = 0.029). However, there were no significant differences between the presence of DISI deformity and fracture location (p = 0.15). Morphologic comparisons by both plain radiography and CT indicated a mean C-T distance in the type I lunate group (22 cases) of 2.3 mm and 5.0 mm in the type II lunate group (48 cases). The C-T distances were significantly correlated with lunate morphology (p = 0.001).

CONCLUSIONS

A type II lunate was associated with low incidence of DISI deformity and proximal location of fracture in patients presenting with a scaphoid nonunion.

Imaging in carpal instability

Carpal instability is a complex and heterogeneous clinical condition. Management requires accurate identification of structural injury with an understanding of the resultant movement (kinematic) and load transfer (kinetic) failure. Static imaging techniques, such as plain film radiography, stress views, ultrasound, magnetic resonance, MR arthrography and computerized tomography arthrography, may accurately depict major wrist ligamentous injury. Dynamic ultrasound and videofluoroscopy may demonstrate dynamic instability and kinematic dysfunction. There is a growing evidence base for the diagnostic accuracy of these techniques in detecting intrinsic ligament tears, but there are limitations. Evidence of their efficacy and relevance in detection of non-dissociative carpal instability and extrinsic ligament tears is weak. Further research into the accuracy of existing imaging modalities is still required. Novel techniques, including four-dimensional computerized tomography and magnetic resonance, can evaluate both cross-sectional and functional carpal anatomy. This is a narrative review of level-III studies evaluating the role of imaging in carpal instability.

Conservative management of midcarpal instability

Midcarpal instability is a complex condition that can present in various forms, from mild pain to debilitating subluxation. Once diagnosed, treatment guidelines for hand therapy are limited by the scarcity of high-level evidence. Evidence does exist for use of proprioceptive awareness and neuromuscular rehabilitation for instability of the knee, shoulder and ankle joint, but studies of similar programmes for the wrist joint have not been published. The purpose of this review is to examine the evidence supporting current concepts in the non-operative management of midcarpal instability, and to provide recommendations for the management of this condition with hand therapy.

Midcarpal instability

Midcarpal instability is a collective term for a number of conditions where the instability of the wrist is predominantly between the proximal and distal carpal rows. It has been regarded as relatively rare and infrequently requires surgical treatment. Palmar midcarpal instability is the most commonly found type of midcarpal instability and can be responsible for causing a clunking and painful wrist. The diagnosis is made on clinical grounds using the midcarpal instability provocative tests. Standard imaging and arthroscopic inspection do not usually confirm a definite diagnosis, but are important in excluding other pathologies. The classification and staging has been described using the extent of palmar translocation of the distal carpal row, which is elicited on passive stress tests. As this is a functional instability, it may be that a functional staging description might be better, and a proposed scheme is described. Treatment options including partial wrist fusions, tenodesis stabilizations and arthroscopic capsular shrinkage have been described in small case series with limited follow-up. There are no comparative series or randomized studies because of the relative rarity of this condition.

Mid-term results of ligament tenodesis in treatment of scapholunate dissociation: a retrospective study of 20 patients

The purpose of this retrospective study was to assess the modified Brunelli technique for the treatment of chronic irreparable complete scapholunate ligament rupture, causing a reducible carpal malalignment without secondary osteoarthritis. A total of 20 patients were treated using this technique. At a mean follow-up period of 24 months (range 6-53, SD 15), pain on a visual analogue scale had improved from 6 (range 3-10) to 3 (range 0-7). Function measured with the DASH score had improved from 37 (range 11-90) to 20 (range 0-53). Range of motion was reduced in flexion by a mean of 19° (range 10-45), and in extension by a mean of 14° (range 0-35). Mean grip strength at last follow-up was 81% of the uninjured hand (range 50-100%) Three patients developed scapholunate advanced collapse (stage II) requiring salvage surgery. Scapholunate ligament reconstruction with the modified Brunelli technique showed satisfactory results in this study. Extended studies are needed to determine the long-term benefits of this reconstructive procedure.

LEVEL OF EVIDENCE

IV.

Association of lesions of the scapholunate interval with arthroscopic grading of scapholunate instability via the geissler classification

PURPOSE

To determine whether specific anatomic lesions of the scapholunate supporting structures are associated with the grades of scapholunate instability according to the Geissler classification.

METHODS

Six fresh frozen cadaveric limbs underwent serial arthroscopic sectioning of the scapholunate supporting ligaments. To simulate a progressive scapholunate injury based on the current literature, sectioning occurred as follows: volar scapholunate interosseous ligament (SLIL), membranous SLIL, dorsal SLIL, radioscaphocapitate, long radiolunate, dorsal radiocarpal, dorsal intercarpal, and scaphotrapeziotrapezoid ligaments. We performed arthroscopic examination of the radiocarpal and midcarpal joints after each ligamentous sectioning and recorded the appearance of the scapholunate interval.

RESULTS

There was a progressive increase in Geissler grade with sequential sectioning of the scapholunate supporting ligaments. In all specimens, Geissler grade 2 injury was associated with sectioning of intrinsic ligaments only. Geissler grade 3 injury first appeared with sectioning through the dorsal SLIL and continued through sectioning of the volar extrinsic ligaments. Geissler grade 4 injury did not occur until the dorsal extrinsic ligaments were sectioned. Statistical analysis indicated a linear relationship between ligament sectioned and Geissler grade, with deeper sections associated with a higher Geissler grade.

CONCLUSIONS

In this cadaveric model, arthroscopically determined Geissler grade was associated with specific anatomic lesions of the scapholunate supporting ligaments. Sequential sectioning of the ligaments showed a progressive increase in Geissler grade.

CLINICAL RELEVANCE

Knowledge of the association of Geissler grade with pathoanatomy may aid the surgeon in deciding which reconstructive method is best.

Chronic scapholunate instability treated with temporary screw fixation

PURPOSE

To determine the efficacy of scapholunate (SL) temporary screw fixation to maintain the reduction of SL interval after ligament debridement, repair, or reconstruction.

METHODS

A total of 36 patients who had chronic SL instability were included. Arthroscopic debridement was performed for dynamic instability, and primary repair or reconstruction of the SL ligament was performed for static instability. We then used SL screw fixation for the protection of the repair or reconstruction. Screws were removed when loosening was noted on x-ray.

RESULTS

The average patient age was 43 years. Eleven had dynamic instability, and 25 had static instability. The average follow-up was 7.9 years. Nearly 95% of the patients had no more than mild pain. The average ranges of movement of the wrist were 55° extension, 51° flexion, 26° ulnar deviation, and 15° radial deviation. Postoperative x-ray revealed an average SL angle of 56°. The average SL gap was 2.5 mm. Both of these radiographic parameters were maintained at final follow-up. Dorsal intercalated segmental instability (DISI) deformity was not corrected in 2 patients. One patient had avascular changes in the proximal scaphoid and lunate but remained asymptomatic at 7 years postoperatively. There was no further intercarpal and radiocarpal degeneration.

CONCLUSIONS

Temporary SL screw fixation together with arthroscopic debridement, ligament repair, or reconstruction provided a stable closure of the SL interval and satisfactory clinical and functional results along with a low incidence of complication.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

The modified Brunelli procedure for scapholunate instability: a single centre study

Management of scapholunate (SL) instability remains controversial. The modified Brunelli procedure is a soft tissue procedure that recreates the stabilising forces of the SL ligament using a split flexor carpi radialis tendon graft passed from volar to dorsal via a tunnel in the distal pole of the scaphoid. Thirteen consecutive patients with an average age of 35 years underwent the modified Brunelli procedure. Pain improved from a mean visual analog score of eight preoperatively to 1.5. The DASH score improved from a preoperative score of 55.4 to 34.9 as did the grip strength from 40% to 75% respectively. All wrist ranges of motion were decreased post-operatively in particular wrist flexion. SL ligament reconstruction using the modified Brunelli procedure resulted in satisfactory outcomes. Post-operatively patients were relatively pain free, with improved grip strength. The range of motion was reduced postoperatively, however did not restrict return to work or premorbid activities.

[Evaluation of a technical modification to Mannerfelt's total wrist fusion technique in a series of 19 rheumatoid wrists]

We studied a technical modification of Mannerfelt's total wrist fusion technique in a series of 19 wrists. A fully intramedullary technique without dorsal carpal fixation was used to protect the extensor tendons. Two intramedullary Rush pins without dorsal staples were used during the arthrodesis procedure. Nineteen rheumatoid arthritis wrists (2 bilateral cases) were reviewed with a mean follow-up of 4.9 years (range 2-10 years). Clinical outcomes were assessed using the VAS pain scale, DASH-score and wrist strength measurements. Wrist fusion was assessed on AP and lateral X-rays of the wrist. The position of the carpal Rush pin entry points and distal hook orientation were also assessed. Pain was 8.9 preoperatively and 1.1 at the last follow-up with 95% patients satisfied. Mean DASH-score was 46.9 points. The pinch strength was 79% and the grip strength was 68% of the contralateral wrist. Carpal height, carpal anterior subluxation and ulnar deviation were stable at the last follow-up. All of the wrists were in straight position and no extensor tendon ruptures were noted. Fusion was complete in all cases within 6 to 12 weeks, except in one case. The technical modification proposed in the current study -intraosseous fixation only- appears to be a good alternative to Mannerfelt's original technique. Every case treated with this modified technique had good functional results and none required pin removal.

The diagnostic accuracy of wrist cineradiography in diagnosing scapholunate dissociation

Ruptures of the scapholunate ligament (SLL) may cause carpal instability, also known as scapholunate dissociation (SLD). SLD may lead to osteoarthritis of the radiocarpal and midcarpal joints. The aim of this retrospective study was to determine the diagnostic value of wrist cineradiography in detecting SLD. All cineradiographic studies made during a 24 year period were retrieved. All patients who underwent the confirmation method (arthroscopy and/or arthrotomy) and cineradiography were included. In total, 84 patients met the inclusion criteria. Sensitivity, specificity, likelihood ratio, positive predictive value, negative predictive value, and diagnostic accuracy for detecting SLD were calculated for radiography and cineradiography. Cineradiography had a sensitivity of 90%, a specificity of 97%, and a diagnostic accuracy of 0.93 in detecting SLD. Radiography had a sensitivity of 81%, a specificity of 80%, and a diagnostic accuracy of 0.81. Cineradiography has a high diagnostic value for diagnosing SLDs. A positive cineradiography markedly increases the post-test probability of SLD.

Dorsal scapholunate stabilization using Viegas' capsulodesis: 25 cases with 26 months-follow-up

Intercarpal instability is often secondary to a scapholunate interosseous (SLIO) ligament lesion. Its reconstruction is thus essential. Classical capsulodesis techniques fix the scaphoid in extension and do not reproduce the physiologic ligamentous isometry of the wrist. The authors use the technique of Viegas, which seems to respect this isometry: the dorsal intercarpal ligament is re-inserted dorsally to reattach the capsule on the dorsal SLIO and to reinforce it. Between 2006 and 2010, 25 wrists were operated on in 12 men and 12 women of mean age 38 years. All patients presented with pain often associated with loss of power, decreased mobility or a debilitating click. The mean follow-up was 26 months. Postoperative and preoperative data were compared. Flexion/extension range increased by 2.6°, radioulnar deviation increased by 21.1°. Grip strength increased by 8.7 kgf. Pain decreased by 3 points on the VAS and the PRWE improved by 59 points. We observed four CRPS, one EPL lesion and one case of superficial track pin infection. We got eleven excellent results, nine good, two moderate and three bad, two of which were re-operated. Viegas' capsulodesis does not present major technical difficulty. The results show no stiffness in flexion/extension. There was evident improvement in radioulnar deviation, grip strength, pain and PRWE scores. This technique provides effective treatment for a difficult or irreparable lesion of the SLIO ligament, without fixed carpal instability corresponding to Geissler arthroscopic stages 2 to 4 and Garcia-Elias stages 3 and 4. The capsulodesis produces an effective stabilization without stiffness. Precautions should be undertaken to avoid CRPS and pin complications.

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.

Scapholunate ligament injury adversely alters in vivo wrist joint mechanics: an MRI-based modeling study

We investigated the effects of scapholunate ligament injury on in vivo radiocarpal joint mechanics using image-based surface contact modeling. Magnetic resonance images of 10 injured and contralateral normal wrists were acquired at high resolution (hand relaxed) and during functional grasp. Three-dimensional surface models of the radioscaphoid and radiolunate articulations were constructed from the relaxed images, and image registration between the relaxed and grasp images provided kinematics. The displacement driven models were implemented in contact modeling software. Contact parameters were determined from interpenetration of interacting bodies and a linear contact rule. Peak and mean contact pressures, contact forces and contact areas were compared between the normal and injured wrists. Also measured were effective (direct) contact areas and intercentroid distances from the grasp images. Means of the model contact areas were within 10 mm(2) of the direct contact areas for both articulations. With injury, all contact parameters significantly increased in the radioscaphoid articulation, while only peak contact pressure and contact force significantly increased in the radiolunate articulation. Intercentroid distances also increased significantly with injury. This study provides novel in vivo contact mechanics data from scapholunate ligament injury and confirms detrimental alterations as a result of injury.

The modified Clayton-Mannerfelt arthrodesis of the wrist in rheumatoid arthritis: operative technique and report on 93 cases

Arthrodesis of a painful and destroyed wrist is one of the key operations in patients with rheumatoid arthritis. Clayton is given credit for the first description of an operative technique of wrist arthrodesis by means of an intramedullary Steinmann pin. Mannerfelt popularized this technique by using a Rush pin and additional fixation with staples. The aim of the present article is to give a detailed description of the operative technique used in our hospital. Over a period of 13 years, 104 modified Clayton-Mannerfelt arthrodeses were performed in 87 patients with rheumatoid arthritis. Ninety-three wrists were reviewed clinically and radiographically. The patients had high fusion rates and a reliable reduction in preoperative pain, with a low rate of complications. The pin technique is more versatile than standard wrist arthrodesis plates, and the wrist can be positioned according to the needs of the patient. This technique seems to be a good alternative to conventional wrist arthrodesis using an arthrodesis plate in wrists destroyed by rheumatoid arthritis, even in situations with difficult bone stock. In most cases, it is not necessary to remove the hardware.

[Treatment of carpal fractures. Recommendations of the Hand Surgery Group of the German Trauma Society]

The primary goal in the treatment of carpal fractures is the preservation of a painless wrist function. Scaphoid fractures are the most common carpal fractures and when such a fracture is clinically suspected CT or MRI scans are usually advisable. Only stable and non-displaced scaphoid fractures can be treated conservatively, all other fractures require internal fixation with restoration of normal anatomy. Second most common are fractures of the triquetrum which can occur as chip avulsions of the dorsal rim and are usually treated symptomatically. Fractures of the body of the triquetrum should be treated according to the degree of instability and displacement. This is virtually true for all carpal bones. Perilunate fracture dislocations of the carpus deserve special attention. In these severe injuries a fracture line can run through all carpal bones but the scaphoid is mostly affected. Accurate reduction and internal fixation by screws and K-wires are indicated not only in these cases, but also in carpometacarpal fracture dislocations.

The diagnosis and treatment of scapholunate instability

Scapholunate instability is the most common form of carpal instability. Pain produced by this condition is caused by the wrist's inability to sustain physiologic loads because of an injury to the linkage between the scaphoid and lunate. The term scapholunate instability may describe a wide spectrum of clinical conditions ranging from mild wrist dysfunction and partial ligamentous tear to debilitating pain with associated rupture of the scapholunate interosseus ligament complex. This article reviews the pathophysiology of scapholunate instability and its identification and treatment.

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.

[Rotatory subluxation of the scaphoid: pathology and surgical management]

The interosseous scapholunate ligament (IOSLL) is the main stabilizer of the scapholunate (SL) couple but a static instability can appear only in the event of an associated injury of the extrinsic ligaments. Thus, SL dissociation covers a broad spectrum in which only static instability leads with certainty to osteoarthritis. Classically described as a rotatory subluxation of the scaphoid with DISI collapse, static SL instability manifests itself as a complex deformity with dorsolateral subluxation of the unit formed by the scaphoid and the distal carpal row. This deformity explains the dorsolateral radioscaphoid conflict and capitolunar decentering that is the origin of the radioscaphoid and midcarpal osteoarthritis that later appears. It is only within the first 4 to 6 weeks that a repair of the IOSLL, possibly associated with a capsulodesis, makes it possible to expect a good result and can prevent osteoarthritis. Beyond that time, no soft tissue procedure will modify the natural history of the condition. For us, surgery is indicated only for acute injuries and for symptomatic chronic instabilities. Before the occurrence of osteoarthritis, with new-found knowledge of the medium-term results of capsulodesis, it seems reasonable to favour a limited fusion. But in the event of failure, the patient is likely to remain in pain even after a total fusion. It is thus not aberrant to perform a capsulodesis in a sedentary person but it is necessary to inform the patient that osteoarthritis will occur. After occurrence of osteoarthritis, if it is symptomatic, proximal row carpectomy, SLAC procedure, total wrist fusion and denervation, can be considered, depending on the stage, the mobility of the wrist and the wishes of the patient. Denervation of the wrist can give good results with few risks, and does not jeopardize the results of a subsequent procedure.

Results of the modified Brunelli tenodesis for treatment of scapholunate instability: a retrospective study of 19 patients

PURPOSE

Management of chronic scapholunate (SL) instability without osteoarthritis remains controversial. In order to recreate an SL interosseous linkage, some surgeons opt for a limited wrist arthrodesis, whereas others use soft tissue stabilization. The purpose of the current study was to review and assess the therapeutic benefit of the modified Brunelli tenodesis that used the flexor carpi radialis tendon to replicate the stabilizing ligaments of the scaphoid.

METHODS

Between 2001 and 2005, 19 tenodesis procedures have been performed to correct dynamic or static SL instability without osteoarthritis. On average, patients had surgery 15 months after injury. The mean follow-up was 37 months.

RESULTS

After surgery, 15 patients had no to mild pain with a mean visual analog scale score of 3 of 10. The average wrist motion was 50 degrees extension, 41 degrees flexion, 24 degrees radial deviation, and 29 degrees ulnar deviation (75%, 73%, 68%, and 86% of the uninvolved wrists, respectively). The grip strength was 78% of the uninvolved wrists. On radiographs, the mean static SL distance was 2.4 mm (2.8 mm before surgery). There was no widening of the SL gap compared to the immediate postoperative gap. The SL angle improved from a mean preoperative value of 61 degrees to 53 degrees immediately after surgery and rose again to 62 degrees at the time of the review. One patient developed a scapholunate advanced collapse wrist stage 2.

CONCLUSIONS

Ligament reconstruction using tendon grafts gave satisfactory results to correct reducible chronic SL instability without osteoarthritis. This repair technique achieved a relatively pain-free wrist, with acceptable grip strength and normal SL distance but with a loss in the arc of motion and a loss of correction of SL angle.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Diagnostic accuracy of plain radiographs and cineradiography in diagnosing traumatic scapholunate dissociation

OBJECTIVE

Missed tears of the scapholunate ligament (SLL) and scapholunate dissociation (SLD) after wrist injuries pose a high risk of post-traumatic osteoarthritis of the carpus. Plain X-rays and dynamic radiographic studies are frequently used for initial diagnostic work-up. Given the limited evidence of their accuracy, we retrospectively compared the radiographic findings of patients with suspected traumatic SLD with wrist arthroscopy as the accepted reference standard.

DESIGN AND METHODS

During a 6-year period, plain radiographs and DSA cineradiography scans were obtained from 198 patients who had sustained a hyperextension injury to their hand. Of those, 102 (72 men, 30 women, mean age of 42+/-12 years) subsequently underwent diagnostic arthroscopy. Digital images were reevaluated by experienced radiologists unaware of the arthroscopic findings for the presence or absence of SLD. We calculated the sensitivity (SN) and specificity (SP) with 95% confidence intervals (CI), and computed areas under the receiver operating characteristic curves (AUC/ROC).

RESULTS

Arthroscopy revealed 42 SLL ruptures, 13, 10, and 19 of which were classified as grade I (partial), II (complete with dynamic instability), or III (complete with static instability) respectively. Plain radiographs correctly identified 24 injuries (SN 57.1%, 95% CI 41.0-72.3%), and produced 1 false-positive result (SP 98.3%, 95% CI 91.1-100.0%). The scapholunate distance and the SL angle contributed independently to the diagnostic variance, with an AUC/ROC of 85.7% (95% CI 76.8-92.2%). Cineradiography had a sensitivity of 36 out of 42 (85.7%, 95% CI 71.5-94.6%), and a specificity of 57 out of 60 (95.0%, 95% CI 86.1-99.0%).

CONCLUSION

Pathological results on plain radiographs and cineradiography reliably indicate the presence of SLD after wrist trauma. Although non-conclusive, a negative dynamic study markedly reduces the pre-test probability of disease. Both methods remain key elements of primary diagnostic strategies for suspected traumatic SLD, and may facilitate the selection of additional tests.

The diagnosis and treatment of scapholunate instability

Scapholunate instability is the most common form of carpal instability. Pain produced by this condition is caused by the wrist's inability to sustain physiologic loads because of an injury to the linkage between the scaphoid and lunate. The term scapholunate instability may describe a wide spectrum of clinical conditions ranging from mild wrist dysfunction and partial ligamentous tear to debilitating pain with associated rupture of the scapholunate interosseus ligament complex. This article reviews the pathophysiology of scapholunate instability and its identification and treatment.

[Early radiological diagnostics for scapholunate dissociation (SLD)]

The partial tear of the scapholunate ligament (pre-dynamic stage of SLD) as well as the complete tear (dynamic stage) does not lead to carpal malalignment. However, if the completely ruptured ligament is accompanied by lesions of the extrinsic ligaments, both the scaphoid and the lunate are malaligned already at rest (static stage of SLD). Later, osteoarthritis will develop, beginning in the radioscaphoid compartment, progressing to the midcarpal joint, and ending in a carpal collapse (osteoarthrotic stage of SLD). Dynamic SLD is detectable only in stress views and in cinematography. The high utility of MRI for directly visualizing the injured ligament is emphasized: reparation tissue is focally enhanced at the rupture site by intravenously applied contrast agent; the individual segments of the scapholunate ligament can be visualized in direct MR arthrography, therefore allowing differentiation of partial and complete ligamentous tears.