[Trans-scapho-perilunar fracture-dislocation: a case report]. / Fractura-luxación transescafo-perilunar: reporte de un caso clínico.

Trans-scaphoid perilunate fractures-dislocations are rare injuries caused by high-energy trauma of the wrist. Diagnosis is based on medical history, physical examination, and tools such as radiographs, computed tomography scan, and magnetic resonance imaging. Early treatment consists of closed reduction and casting to stabilize the limb. Definitive treatment is surgical and includes bone and soft tissue repair. A case of trans-scaphoid perilunate fracture-dislocation is presented, along with diagnosis, management and outcome.

Las fracturas-luxaciones transescafo-perilunares son lesiones infrecuentes causadas por impactos de alta energía hacia la muñeca. El diagnóstico se basa en la historia clínica, exploración física y herramientas como la radiografía, la tomografía computarizada y la resonancia magnética. El manejo inmediato consiste en una reducción cerrada e inmovilización para estabilizar la extremidad. El tratamiento definitivo es de carácter quirúrgico e incluye la reparación ósea y de tejidos blandos. Se presenta un caso de fractura-luxación transescafo-perilunar, su diagnóstico, manejo y evolución.

Detection of scapholunate interosseous ligament injury using dynamic computed tomography-derived arthrokinematics: A prospective clinical trial.

Scapholunate interosseous ligament injuries are a major cause of wrist instability and can be difficult to diagnose radiographically. To improve early diagnosis of scapholunate ligament injuries, we compared injury detection between bilateral routine clinical radiographs, static CT, and dynamic four-dimensional CT (4DCT) during wrist flexion-extension and radioulnar deviation. Participants with unilateral scapholunate ligament injuries were recruited to a prospective clinical trial investigating the diagnostic utility of 4DCT imaging for ligamentous wrist injury. Twenty-one participants underwent arthroscopic surgery to confirm scapholunate ligament injury. Arthrokinematics, defined as distributions of interosseous proximities across radioscaphoid and scapholunate articular surfaces at different positions within the motion cycle, were used as CT-derived biomarkers. Preoperative radiographs, static CT, and extrema of 4DCT were compared between uninjured and injured wrists using Wilcoxon signed rank or Kolmogorov-Smirnov tests. Median interosseous proximities at the scapholunate interval were significantly greater in the injured versus the uninjured wrists at static-neutral and maximum flexion, extension, radial deviation, and ulnar deviation. Mean cumulative distribution functions at the radioscaphoid joint were not significantly different between wrists but were significantly shifted at the scapholunate interval towards increased interosseous proximities in injured versus uninjured wrists in all positions. Median and cumulative distribution scapholunate proximities from static-neutral and 4DCT-derived extrema reflect injury status.

Isolated Unilateral Absence of Lunate: A Case Report and Review of Literature.

Isolated unilateral absence of lunate is an extremely rare condition with only one such case reported in English literature so far. The rarity of this condition can lead to diagnostic dilemma, especially if patient has an old history of trauma or surgery around the wrist, leading to unnecessary intervention and difficulty in ensuring a good surgical outcome. We present such a case and discuss the clinical pointers to the diagnosis of this condition. Level of Evidence: Level V (Therapeutic).

Small volar fragment in the lunate fossa leads to volar tilt loss after volar plate fixation for AO/OTA type-C distal radius fracture.

OBJECTIVES: The relationship between volar fragment size and postoperative volar tilt loss in complete articular distal radius fracture is not well known. In this study, we measured precise radiological parameters to help identify other factors that might contribute to volar tilt loss. MATERIAL AND METHODS: We retrospectively reviewed the radiological examinations and charts of 256 patients with distal radial fracture who underwent volar locking plate fixation between March 2014 and July 2022. Radiological parameters were measured based on preoperative CT and immediate postoperative radiographs. Univariate and multivariate linear regression analysis was performed to identify relevant factors associated with volar tilt loss following volar locking plate fixation. The receiver operating characteristic curve was used to identify the cutoff value of the independent parameters. RESULTS: On univariate analysis, 2 radiologic parameters on preoperative CT (volar fragment length at the lunate fossa, and teardrop angle) and 4 on immediate postoperative X-ray (radial inclination, radial length, capitate shift, and volar tilt) were significantly associated with postoperative volar tilt loss. On multivariate linear regression analysis, the risk of volar tilt loss increased as the capitate moved toward the back of the radial shaft. The cut-off for anteroposterior length in the lunate fossa was 6.5 mm. CONCLUSIONS: AO/OTA type-C distal radius fractures with <6.5 mm anteroposterior length in the lunate fossa had significantly higher rates of malunion with dorsal deformity. In addition, preoperative teardrop angle <37.2 ° and immediate postoperative volar tilt <3.7º are also predictors of postoperative volar tilt loss.

Scaphoid proximal pole ejection in perilunate injury: a case report and pathophysiological hypothesis.

Isolated ejection of the scaphoid proximal pole in perilunate injuries is rare, with only 4 reports in the literature, and does not correspond to the biomechanical situations in the Herzberg or Mayfield classifications. Bone ejection incurs a risk of avascular necrosis despite good osteosynthesis, notably because of precarious vascularization. We present a case of scaphoid proximal pole ejection and a theoretical hypothesis of the biomechanics of this injury. LEVEL OF EVIDENCE: 4.

One-Year Outcomes of the Anatomical Front and Back Reconstruction for Scapholunate Dissociation.

PURPOSE: Anatomical front and back (ANAFAB) reconstruction addresses the critical volar and dorsal ligaments associated with scapholunate dissociation. We hypothesized that patients with symptomatic, chronic, late-stage scapholunate dissociation would demonstrate improvements in all radiographic parameters and patient-reported outcomes (PROMs) after ANAFAB reconstruction. METHODS: From 2018 to 2021, 21 ANAFAB reconstructions performed by a single surgeon were followed prospectively, with 20 patients having a minimum follow-up of 12 months. In total, 17 men and four women were included, with an average age of 49 years. Three patients had modified Garcia-Elias stage 3 disease, eight stage 4, seven stage 5, and three stage 7. ANAFAB reconstruction of intrinsic and extrinsic ligament stabilizers was performed using a hybrid synthetic tape/tendon graft in a transosseous reconstruction. Pre- and postoperative radiographic parameters, grip, pinch strength, the Patient-Rated Wrist Evaluation, PROMIS Upper Extremity Function, and PROMIS Pain Interference outcome measures were compared. RESULTS: Mean follow-up was 17.9 months (range: 12-38). Radiographic parameters were improved at follow-up, including the following: scapholunate angle (mean 75.3° preoperatively to 69.2°), scapholunate gap (5.9-4.2 mm), dorsal scaphoid translation (1.2-0.2 mm), and radiolunate angle (13.5° to 1.8°). Mean Patient-Rated Wrist Evaluation scores for pain and function decreased from 40.6 before surgery to 10.4. We were unable to detect a significant difference in grip or pinch strength or radioscaphoid angle with the numbers tested. There were two minor complications, and two complications required re-operations, one patient who was converted to a proximal row carpectomy for failure of fixation, and one who required tenolysis/arthrolysis for arthrofibrosis. CONCLUSIONS: At 17.9-month average follow-up, radiographic and patient-reported outcome parameters improved after reconstruction of the critical dorsal and volar ligament stabilizers of the proximal carpal row with the ANAFAB technique. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Radiographic evaluation of radial flexion osteotomy effect on static scapholunate instability: a preliminary cadaveric study.

INTRODUCTION: The optimal treatment of chronic scapholunate instability has yet to be established. Scapholunate ligament grafts are still far from being the ideal solution. We conducted an experimental study to evaluate whether flexion-opening wedge osteotomy of the distal radius improves misalignment and avoids rotatory subluxation of the scaphoid in a cadaveric model of static scapholunate dissociative instability. MATERIALS AND METHODS: Radiographic studies were performed on 15 cryopreserved specimens after recreating a model of scapholunate instability by division of the scapholunate interosseous ligament (SLIL) and secondary stabilizers, taking radiographs at baseline, after the instability model, and after distal radius osteotomy. Static and dynamic (under controlled tendon traction) anteroposterior and lateral views were obtained to measure the length (in mm) of the carpal scaphoid and scapholunate interval, scapholunate angle, radio-lunate angle, and palmar tilt of the distal joint surface of the radius and to measure the dorsal scaphoid translation by the concentric circles method. The Wilcoxon test was used for statistical comparisons. RESULTS: The scapholunate interval was significantly decreased after osteotomy in all static anteroposterior views and in all lateral views under tendon traction. Dorsal scaphoid translation was significantly reduced in static lateral view in extension and in dynamic lateral view under 5-pound flexor carpi radialis tendon tension controlled by a digital dynamometer. CONCLUSIONS: Flexion-addition osteotomy of the distal radius appears to improve carpal alignment parameters in a cadaveric model of static scapholunate instability, achieving similar values to those obtained before instability.

Ligamentoplasty in scapholunate instability: short-term results of the "all dorsal scapholunate repair" technique.

Injury to the scapholunate complex is the cause of scapholunate instability which can lead to radiocarpal and medio-carpal osteoarthritis. Several ligamentoplasty techniques have been reported for the treatment of chronic scapholunate instability before the osteoarthritis stage. The objective of this study was to assess the short-term results of an "all dorsal scapholunate repair" ligamentoplasty. We report the clinical, radiological and functional results of a retrospective study including 21 patients, operated between June 2019 and December 2020 for a stage 3 or 4 scapholunate instability according to the Garcia Elias classification. With a follow-up of 14.2 months, the pain was 0.1/10 according to the VAS at rest and 4/10 during exercise. Wrist strength was measured at 65% of the opposite side. The flexion-extension range of motion was 105°. Radiologically, there was a reduction of the diastasis and scapholunate angle. Osteolysis areas around the anchors were described in 47% of patients. The mean QuickDASH was 29.2/100, PRWE 24/100 and Mayo wrist score 67.8/100. Eighty-one percent of patients were satisfied. Seventeen patients had returned to work 5.2 months postoperatively. In the case of work-related injury, the functional scores were poorer, with a delayed return to work. This technique provides encouraging results in the short term. Most patients were improved compared to preoperative state. The work-related injury appears to be a poor prognostic factor. A longer-term study is imperative to confirm the maintenance over time of the correction of carpal malalignment and the evolution of the osteolysis areas.Level of evidence: Level IV Retrospective study.

Anatomical front and back reconstruction sustains radiographic alignment: a comparison to three-ligament tenodesis.

Multiple techniques exist to reconstruct the scapholunate interosseous ligament, though none have demonstrated superiority. This study compares 1-year radiographic outcomes of the three-ligament tenodesis and the anatomical front and back reconstruction. All patients who underwent reconstruction of their scapholunate interosseous ligament at one institution with either anatomical front and back reconstruction or three-ligament tenodesis between 2011 and 2020 were retrospectively reviewed. At 52-week follow-up, anatomical front and back reconstruction maintained a statistically significant improvement in scapholunate gap, corrected radiolunate angle and dorsal scaphoid translation, while three-ligament tenodesis demonstrated no sustained improvement in any parameter. The improvement in dorsal scaphoid translation was significantly greater for patients undergoing anatomical front and back reconstruction compared with three-ligament tenodesis at the 16-weeks postoperative timepoint (-1.0 mm, -0.3 mm). Anatomical front and back reconstruction demonstrates sustained improvement in radiographic outcomes at 1 year when compared with three-ligament tenodesis. By addressing both volar and dorsal critical ligament restraints, adoption of anatomical front and back reconstruction for advanced stage scapholunate interosseous ligament injuries should be considered.Level of evidence: IV.

Osteolysis After Augmented Scapholunate Ligament Reconstruction: A Report of 3 Cases.

CASE: Augmented scapholunate ligament reconstruction using polyether ether ketone anchors and ultra-high molecular weight polyethylene synthetic tape has the theoretical advantage of improved stability, avoidance of K-wire fixation, and the potential for earlier mobilization. We present 3 cases of scaphoid and lunate osteolysis/fragmentation, operative and histologic findings at reoperation, and the sequelae of this technique. CONCLUSION: If planning to use suture anchors and synthetic tapes in small carpal bones, we recommend advising patients about the risk of osteolysis and monitoring closely patients who complain of pain with motion after surgery.

Anterior dislocation of the lunate due to a high-energy trauma.

Semilunate and perilunate dislocation is an injury that mostly occurs when the subject is exposed to a high-energy trauma. Considered severe, it compromises the stability and function of the wrist. The case presented is that of a 50-year-old male patient who after having a motorcycle accident arrived at the ER with neurovascular affectation, swelling, deformity and a considerable decrease of the wrist joint movement. He was also referring severe pain. A Henry (Volar) intervention was done with the help of external fixation of the lunate, followed by K-wire fixation, once a prior closed reduction was unsuccessfully attempted. The scaphoid was connected to the semilunate, and then the latter with the capitate. Ligament reconstruction followed, and stability was clinically confirmed with an X-ray. Although improvement of symptomatology was observed during the follow-up analysis, motion of the wrist remained limited. Even with the best treatment, in terms of functionality, this type of injury presents a poor prognosis.

La luxación semilunar y perilunar es una lesión que se produce principalmente cuando el sujeto está expuesto a un traumatismo de alta energía. Considerada grave, compromete la estabilidad y la función de la muñeca. El caso presentado es el de un paciente varón de 50 años que tras sufrir un accidente de motocicleta llegó a urgencias con afectación neurovascular, tumefacción, deformidad y una considerable disminución del movimiento articular de la muñeca. También refería fuertes dolores. Se realizó una intervención de Henry (Volar) con la ayuda de fijación externa del lunar, seguida de fijación con agujas de Kirschner, una vez que se había intentado sin éxito una reducción cerrada previa. El escafoides se conectó con el semilunar y luego éste con el capitado. A continuación se reconstruyó el ligamento y se confirmó clínicamente la estabilidad con una radiografía. Aunque se observó una mejora de la sintomatología durante el análisis de seguimiento, el movimiento de la muñeca seguía siendo limitado. Incluso con el mejor tratamiento, en términos de funcionalidad, este tipo de lesión presenta un mal pronóstico.

Evaluation of a newly designed deep learning-based algorithm for automated assessment of scapholunate distance in wrist radiography as a surrogate parameter for scapholunate ligament rupture and the correlation with arthroscopy.

PURPOSE: Not diagnosed or mistreated scapholunate ligament (SL) tears represent a frequent cause of degenerative wrist arthritis. A newly developed deep learning (DL)-based automated assessment of the SL distance on radiographs may support clinicians in initial image interpretation. MATERIALS AND METHODS: A pre-trained DL algorithm was specifically fine-tuned on static and dynamic dorsopalmar wrist radiography (training data set n = 201) for the automated assessment of the SL distance. Afterwards the DL algorithm was evaluated (evaluation data set n = 364 patients with n = 1604 radiographs) and correlated with results of an experienced human reader and with arthroscopic findings. RESULTS: The evaluation data set comprised arthroscopically diagnosed SL insufficiency according to Geissler's stages 0-4 (56.5%, 2.5%, 5.5%, 7.5%, 28.0%). Diagnostic accuracy of the DL algorithm on dorsopalmar radiography regarding SL integrity was close to that of the human reader (e.g. differentiation of Geissler's stages ≤ 2 versus > 2 with a sensitivity of 74% and a specificity of 78% compared to 77% and 80%) with a correlation coefficient of 0.81 (P < 0.01). CONCLUSION: A DL algorithm like this might become a valuable tool supporting clinicians' initial decision making on radiography regarding SL integrity and consequential triage for further patient management.

Suture Anchor Fixation for Lunate Osteochondral Shear Fracture: A Case Report.

CASE: A 26-year-old right-hand-dominant man sustained a left transradial, translunate perilunate injury after motor vehicle collision. The proximal lunate fractured a primarily cartilaginous 15 × 15 mm osteochondral shear fragment with 40% articular surface involvement. A novel lunate fracture suture anchor fixation technique is described, which led to fracture healing. The radial styloid was treated with a single screw. CONCLUSION: Translunate perilunate injuries involving the lunate proximal articular surface are rare. Treatment recommendations are limited to case reports. Suture anchor fixation led to stable fixation and fracture healing at the final 6-month postoperative follow-up.

Scaphoid, lunate and capitate kinematics in the normal and ligament deficient wrist: A bi-plane X-ray fluoroscopy study.

The ligamentous structures of the wrist stabilise and constrain the interactions of the carpal bones during active wrist motion; however, the three-dimensional translations and rotations of the scaphoid, lunate and capitate in the normal and ligament deficient wrist during planar and oblique wrist motions remain poorly understood. This study employed a computer-controlled simulator to replicate physiological wrist motion by dynamic muscle force application, while carpal kinematics were simultaneously measured using bi-plane x-ray fluoroscopy. The aim was to quantify carpal kinematics in the native wrist and after sequential sectioning of the scapholunate interosseous ligament (SLIL) and secondary scapholunate ligament structures. Seven fresh-frozen cadaveric wrist specimens were harvested, and cycles of flexion-extension, radial-ulnar deviation and dart-thrower's motion were simulated. The results showed significant rotational and translational changes to these carpal bones in all stages of disruptions to the supporting ligaments (p < 0.05). Specifically, following the disruption of the dorsal SLIL (Stage II), the scaphoid became significantly more flexed, ulnarly deviated, and pronated relative to the radius, whereas the lunate became more extended, supinated and volarly translated (p < 0.05). Sectioning of the dorsal intercarpal (DIC), dorsal radiocarpal (DRC), and scaphotrapeziotrapezoid (STT) ligaments (Stage IV) caused the scaphoid to collapse further into flexion, ulnar deviation, and pronation. These findings highlight the importance of all the ligamentous attachments that relate to the stability of the scapholunate joint, but more importantly, the dorsal SLIL in maintaining scapholunate stability, and the preservation of the attachments of the DIC and DRC ligaments during dorsal surgical approaches. The findings will be useful in diagnosing wrist pathology and in surgical planning.

Comminuted lunate fracture combined with distal radius fracture and scaphoid fracture: A case report.

RATIONALE: Incidence of lunate fractures is very low, less than 1% of all fractures. Lunate fractures generally come from high-energy injuries, often combined with other wrist fractures. Simple lunate fractures can be fixed with screws or Kirschner wires. However, Comminuted lunate fractures are difficult to reduce and fixe by conventional methods. PATIENT CONCERNS: Here we report a 42-year-old male construction worker who was crushed by an excavator bucket and presented with comminuted lunate fracture combined with distal radius fracture and scaphoid fracture. DIAGNOSES: Comminuted lunate fracture, distal radius fracture, and scaphoid fracture. INTERVENTIONS: The posterior approach was used to reconstruct the radial lunate bone with polymethylmethacrylate cement, and cannulated screws were used to fix the scaphoid and distal radius fractures. OUTCOMES: At the 3rd month after surgery, the movement of the right wrist joint improved. At the sixth month after surgery, the patient returned to the building site and began working at the same intensity as before the injury. LESSONS: Although the incidence of comminuted lunate fractures is very low, they occur sometimes. For comminuted lunate fractures, early identification and intervention can preserve most of the function of the wrist joint.

A novel classification of Kienbock's disease based on magnetic resonance imaging.

PURPOSE: We devised a classification system for Kienbock's disease using magnetic resonance imaging (MRI). Moreover, we compared it with the modified Lichtman classification and evaluated the inter-observer reliability. METHODS: Eighty-eight patients diagnosed with Kienbock's disease were included. All patients were classified using the modified Lichtman and MRI classifications. MRI staging was based on factors including partial marrow oedema, cortical integrity of the lunate, and dorsal subluxation of the scaphoid. The inter-observer reliability was evaluated. We also evaluated the presence of a displaced coronal fracture of the lunate and investigated its association with the presence of a dorsal subluxation of the scaphoid. RESULTS: Seven patients were categorized into stage I, 13 into II, 33 into IIIA, 33 into IIIB, and two into IV using the modified Lichtman classification. Six patients were categorized into stage I, 12 into II, 56 into IIIA, ten into IIIB, and four into IV using the MRI classification. The greatest shift between the stages was observed in stages IIIA and IIIB when the results of the two classification systems were compared. The inter-observer reliability of the MRI classification was greater than that of the modified Lichtman classification. Fifteen cases with a displaced coronal fracture of the lunate were identified, and a dorsal subluxation of the scaphoid was significantly more present in these patients. CONCLUSION: The MRI classification system is more reliable than is the modified Lichtman classification. MRI classification reflects carpal misalignment with higher fidelity and is more appropriate for classification into stages IIIA and IIIB.

Artificial Lunate Arthroplasty for Kienböck Disease With Multiple Extensor Tendon Ruptures: A Case Report.

CASE: A 73-year-old woman presented with wrist pain and loss of extension in the middle and ring fingers. Radiography revealed a dorsally displaced lunate fragment, resulting in a diagnosis of Kienböck disease with extensor tendon rupture. Artificial lunate replacement and tendon transfer were performed as treatment. Two years postoperatively, the pain was relieved, and the extension lag was 0°. The wrist motion and carpal height had also improved. CONCLUSION: Lunate excision, partial wrist arthrodesis, or proximal row carpectomy are known treatments for Kienböck disease with extensor tendon rupture. Lunate arthroplasty is a novel, useful treatment option for this condition.

Scapholunate ligament injuries: an instructional review for the FRCS examination.

An instructional review of the anatomy, investigation, and management of scapholunate ligament injuries. Aimed at the knowledge level required for the trauma and orthopaedic FRCS examination.

Scapho-luno-capitate fusion with proximal lunate articular surface preservation for management of grade IIIA Kienböck's disease: a prospective case series.

BACKGROUND: Kienböck's disease is idiopathic lunate avascular necrosis, which may lead to lunate collapse, abnormal carpal motion and wrist arthritis. The current study aimed to assess the outcomes of treating stage IIIA Kienböck's disease by a novel technique of limited carpal fusion via partial lunate excision with preservation of the proximal lunate surface and scapho-luno-capitate (SLC) fusion. MATERIALS AND METHODS: We conducted a prospective study of patients with grade IIIA Kienböck's disease managed with a novel technique of limited carpal fusion comprising SLC fusion with preservation of the proximal lunate articular cartilage. Autologous iliac crest bone grafting and K-wires fixation were used to enhance the osteosynthesis of the SLC fusion. The minimum follow-up period was 1 year. A visual analog scale (VAS) and the Mayo Wrist Score were utilized for the evaluation of patient residual pain and functional assessment, respectively. A digital Smedley dynamometer was used to measure the grip strength. The modified carpal height ratio (MCHR) was used for monitoring carpal collapse. The radioscaphoid angle, scapholunate angle, and the modified carpal-ulnar distance ratio were used for the assessment of carpal bones alignment and ulnar translocation of carpal bones. RESULTS: This study included 20 patients with a mean age of 27.9 ± 5.5 years. At the last follow-up, the mean range of flexion/extension range of motion (% of normal side) improved from 52.8 ± 5.4% to 65.7 ± 11.1%, P = 0.002, the mean grip strength (% of normal side) improved from 54.6 ± 11.8% to 88.3 ± 12.4%, P = 0.001, the mean Mayo Wrist Score improved from 41.5 ± 8.2 to 81 ± 9.2, P = 0.002, and the mean VAS score reduced from 6.1 ± 1.6 to 0.6 ± 0.4, P = 0.004. The mean follow-up MCHR improved from 1.46 ± 0.11 to 1.59 ± 0.34, P = 0.112. The mean radioscaphoid angle improved from 63 ± 10º to 49 ± 6º, P = 0.011. The mean scapholunate angle increased from 32 ± 6º to 47 ± 8º, P = 0.004. The mean modified carpal-ulnar distance ratio was preserved and none of the patients developed ulnar translocation of the carpal bones. Radiological union was achieved in all patients. CONCLUSIONS: Scapho-luno-capitate fusion with partial lunate excision and preservation of the proximal lunate surface is a valuable option for treating stage IIIA Kienböck's disease, with satisfactory outcomes. Level of evidence Level IV. Trial registration Not applicable.

A Novel Surgical Technique for Neglected Volar Dislocation of the Lunate: Cases Report and Literature Review.

BACKGROUND: Treatments for chronic perilunate or lunate dislocations are very difficult and associated with poor prognoses. There is no established treatment method and are still many controversies. CASE PRESENTATION: We reported three cases of chronic neglected lunate volar dislocation treated with a novel surgical technique. All three cases were males with wrist pain and tingling sensation. Radiographs confirmed chronic volar dislocation of the lunate. Open reduction was performed by combined volar and dorsal approaches. After anatomical reduction, scapholunate and lunotriquetral interosseous ligament reconstructions were performed with the palmaris longus tendon and synthetic tape. The patients had an uneventful postoperative period with satisfactory functional outcomes at the last follow-up. CONCLUSIONS: We believe that open reduction and interosseous ligament reconstruction using the autogenous tendon and synthetic tape may be a valuable option for treating chronic volar dislocation of the lunate.