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.

Scapholunate Instability: Diagnosis and Management - Anatomy, Kinematics, and Clinical Assessment - Part I.

Injuries to the scapholunate joint are the most frequent cause of carpal instability. The sequelae of these injuries account for considerable morbidity, and if left untreated, may lead to scapholunate advanced collapse and progressive deterioration of the carpus. Rupture of the scapholunate interosseous ligament and its critical stabilizers causes dyssynchronous motion between the scaphoid and lunate. Additional ligament injury or attenuation leads to rotary subluxation of the scaphoid and increased scapholunate gap. Intervention for scapholunate instability is aimed at halting the degenerative process by restoring ligament integrity and normalizing carpal kinematics. In the first section of this review, we discuss the anatomy, kinematics, and biomechanical properties of the scapholunate ligament as well as its critical ligament stabilizers. We provide a foundation for understanding the spectrum of scapholunate ligament instability and incorporate meaningful new anatomical insights that influence treatment considerations. The purpose is to provide an update regarding the anatomy of the scapholunate ligament complex, importance of the critical ligament stabilizers of the proximal carpal row, introduction of safe technique to surgically expose the scaphoid and lunate, as well as pathoanatomy as it pertains to the treatment of scapholunate dissociation. In the second section of this review, we propose a novel ligament-based treatment algorithm based on the stage of injury, degree and nature of ligament damage, and presence of arthritic changes.

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.

Comparison of Radiographic and Intraoperative Visual Assessment of Scaphotrapezoid Joint Arthritis in Patients With End-Stage Carpometacarpal Arthritis of the Thumb Base.

Background: The purpose of this investigation is to compare the radiographic and intraoperative assessment of scaphotrapezoid (ST) joint arthritis in patients with end-stage carpometacarpal (CMC) arthritis of the thumb base. We aim to define the incidence of ST arthritis in this population and determine whether radiographic features such as lunate morphology, dorsal intercalated segment instability (DISI), and scapholunate (SL) diastasis are associated with the incidence of ST arthritis. Methods: We retrospectively reviewed consecutive patients with end-stage CMC arthritis of the thumb treated operatively with trapeziectomy. Preoperative wrist radiographs were reviewed, and the presence of ST arthritis was determined using the Sodha classification. Lunate morphology, DISI, and SL diastasis were noted. Intraoperative grading of ST arthritis was assessed using a modified Brown classification. The specificity and sensitivity of radiographic assessment was compared with the gold standard of intraoperative direct visualization. Results: In total, 302 thumbs met inclusion criteria. End-stage ST joint arthritis determined by intraoperative visual inspection was noted in 31% of cases. No radiographic or demographic variables were found to be risk factors for ST arthritis. Plain radiographs were 47% sensitive and 94% specific in their ability to detect end-stage ST joint arthritis. Conclusions: We report a 31% incidence of end-stage ST joint arthritis in surgically treated patients with CMC arthritis based on visual inspection which is lower than previous literature. Wrist radiographs demonstrate a 47% sensitivity and 94% specificity in predicting end-stage ST joint arthritis. It is imperative to directly visualize the ST joint after trapeziectomy, as radiographs demonstrate poor sensitivity.

Kienböck Disease: Recent Advances in the Basic Science, Assessment and Treatment.

Kienböck disease is a disorder of impaired lunate vascularity which ultimately has the potential to lead to marked degeneration of the wrist and impaired wrist function. The aetiology of the avascular necrosis is uncertain, but theories relate to ulnar variance, variability in lunate vascularity and intraosseous pressures. Clinical symptoms can be subtle and variable, requiring a high index of suspicion for the diagnosis. The Lichtmann classification has historically been used to guide management. We present a review of Kienböck disease, with a focus on the recent advances in assessment and treatment. Based on our understanding thus far of the pathoanatomy of Kienböck's disease, we are proposing a pathological staging system founded on the vascularity, osseous and chondral health of the lunate. We also propose an articular-based approach to treatment, with an arthroscopic grading system to guide management.

Dynamic assessment of wrist after proximal row carpectomy and 4-corner fusion.

PURPOSE: To investigate the effect of 4-corner fusion (4CF) or proximal row carpectomy (PRC) on wrist motion, strength, and outcome for 2 different cohorts from 2 separate institutions performing either 4CF or PRC for stage 2/3 scaphoid nonunion advanced collapse and scapholunate advanced collapse. METHODS: The researchers assessed 46 subjects (24 4CF and 22 PRC), mean age 54 years, with a flexible electrogoniometer to measure maximum wrist motion and circumduction and compare it with the nonsurgical wrist. We analyzed the shape, size, rate, and smoothness of the circumduction curves. We assessed the maximum grip and sustainability of grip for 60 seconds using a digital grip analyzer. Patient evaluation measure and Michigan Hand Questionnaires measured patient-reported outcomes. RESULTS: Flexion-extension in the surgically treated wrist was 50% of the nonsurgical side after a 4CF and 65% after a PRC. The radioulnar deviation component in circumduction of the surgically treated wrist was similar but markedly decreased after either procedure. The mean area of circumduction of the surgically treated wrist was similar after a PRC and a 4CF but was 30% of the nonsurgical wrist. The center of the circumduction ellipse after a PRC was closer than after a 4CF to the opposite wrist. The orientation of the plane of circumduction was 22° to the vertical flexion-extension plane after a PRC. After a 4CF, the plane was more vertical (9°). The peak grip strength and the area under the force time curve was 80% of the nonsurgical side after a PRC and 60% after a 4CF. The Michigan Hand Questionnaire result was 90% of the score for the nonsurgical hand after a PRC and 75% of score for the nonsurgical hand after a 4CF. CONCLUSIONS: The PRC provided improved flexion-extension with a circumduction curve concentric with the nonsurgical wrist. The 4CF limited extension and ulnar deviation more than did a PRC. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Proximal row carpectomy versus scaphoid excision and intercarpal arthrodesis: intraoperative assessment and procedure selection.

PURPOSE: To demonstrate the relative frequency of degenerative changes of the radiolunate and capitolunate joints in osteoarthritis of the wrist as seen by direct visualization, and to demonstrate the disparity between findings on preoperative radiographs and direct visualization. METHODS: We reviewed 18 consecutive patients who underwent either a proximal row carpectomy (PRC) or a scaphoid excision and 4-corner arthrodesis (SEFCA) for symptomatic degenerative arthritis of the wrist. In each case, the articular surfaces of the radiolunate and capitolunate joints were inspected intraoperatively; based on the relative degree of degenerative changes, either a PRC or an SEFCA was performed. We compared preoperative radiographs and the predicted procedure based on them with intraoperative findings and the procedure actually performed. RESULTS: Of 18 wrists, 15 had more severe degenerative changes on the proximal articular surface of the lunate than on the capitate head and underwent a PRC; the remaining 3 had more severe changes on the capitate head than on the proximal surface of the lunate and underwent an SEFCA. In contrast, preoperative radiographs in 13 of the 18 cases revealed degenerative changes at the capitolunate joint and minimal or no changes at the radiolunate joint. An SEFCA was the predicted procedure in all 13, but was performed in 3. The remaining 10 underwent a PRC. CONCLUSIONS: Preoperative radiographs did not correlate well with intraoperative findings in the assessment of degenerative changes at the radiolunate and capitolunate joints, with changes at the radiolunate joint often underestimated. Our findings contradict the widely held contention that the radiolunate joint is consistently spared in osteoarthritis. The lunate fossa of the radius appears to be consistently spared, but not the proximal surface of the lunate. We recommend intraoperative assessment of the articular surfaces, rather than preoperative radiographs, for selection of the surgical procedure. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

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.

Arthroscopic assessment of avascular necrosis.

Avascular necrosis of the lunate is a process that is not well understood. The cause is uncertain, but a common theory persists that it is caused by disruption of the vascular supply to the lunate. This article discusses an approach to assessment that respects the articular cartilage and places at the front of the decision-making process the pathoanatomic components of the articular cartilage. It primarily respects the articular cartilage in the patient with avascular necrosis. This approach was developed for avascular necrosis of the lunate, but in principle applies to other joints with avascular necrosis as well.

Objective assessment of the alterations in wrist mobility with the fastrak(®) system following dorsal capsulodesis.

The treatment for scapholunate dissociation is challenging and its management is varied depending on type, severity and duration of injury, and surgeon's preferred technique. This study aimed to objectively assess the variations in the range and patterns of wrist movements using the Fastrak(®) system in patients having undergone Blatt's dorsal capsulodesis (BDC). The wrist movements were successively measured between the operated and unoperated wrists, while the patients performed set tasks. Seventeen patients agreed to participate in the study. Following BDC the mean flexion loss was 23° (range 10°-38°). However, functional tasks revealed that the BDC did not adversely affect the function of the operated wrist. This novel study demonstrates objectively the functional restrictions that patients are likely to experience postoperatively following BDC. It would be interesting to note the pattern of wrist motion using the Fastrak(®) system in various other clinical settings.

A biomechanical assessment of the coupling of torsion and tension in the human scapholunate ligament.

The mechanical behaviour of human scapholunate ligaments is not well described in the literature with regard to torsion. In this study, intact scapholunate specimens were mechanically tested in torsion to determine whether a simultaneous tensile load was generated. Human intact scapholunate specimens (n = 19) were harvested. The scaphoid and lunate bones were potted in square chambers using epoxy cement, while the interposing ligament remained exposed. Each specimen was mounted rigidly in a specially designed test jig and remained at a fixed axial length during all tests. Specimens were subjected to a torsional load regime that included cyclic preconditioning, ramp-up, stress relaxation, ramp-down, rest, and torsion to failure. Torque and axial tension were monitored simultaneously. The relationship between torsion and tension was determined. Graphs of torque versus tension were generated, from which outcome measures were extracted. Tests demonstrated a clear relationship between applied torsion and the resulting generation of tension for the ligament during ramp-up (torsion-to-tension ratio, 38.86 +/- 29.00 mm; linearity coefficient R2 = 0.89 +/- 0.15; n = 19), stress relaxation (torsion-to-tension ratio, 23.43 +/- 15.84 mm; R2 = 0.90 +/- 0.09; n = 16), and failure tests (torsion-to-tension ratio, 38.81 +/- 26.39mm; R2 = 0.77 +/- 0.20; n = 16). No statistically significant differences were detected between the torsion-to-tension ratios (p = 0.13) or between the linearity (R2) of the best-fit lines (p > 0.085). A strongly coupled linear relationship between torsion and tension for the scapholunate ligament was exhibited in all test phases. This may suggest interplay between these two parameters in the stabilization of the ligament during normal motion and for injury cascades.

Assessment of four midcarpal radiologic determinations.

Several radiologic measurement methods have been described for determining static carpal alignment of the wrist. These include the scapholunate, radiolunate, and capitolunate angles. The triangulation method is an alternative radiologic measurement which we believe is easier to use and more reproducible and reliable than the above mentioned methods. The purpose of this study is to assess the intraobserver reproducibility and interobserver reliability of the triangulation method, scapholunate, radiolunate, and capitolunate angles. Twenty orthopaedic residents and staff at varying levels of training made four radiologic measurements including the scapholunate, radiolunate and capitolunate angles as well as the triangulation method on five different lateral, digitized radiographs of the wrist and forearm in neutral radioulnar deviation. Thirty days after the initial measurements, the participants repeated the four radiologic measurements using the same radiographs. The triangulation method had the best intra-and-interobserver agreement of the four methods tested. This agreement was significantly better than the capitolunate and radiolunate angles. The scapholunate angle had the next best intraobserver reproducibility and interobserver reliability. The triangulation method has the best overall observer agreement when compared to the scapholunate, radiolunate, and capitolunate angles in determining static midcarpal alignment. No comment can be made on the validity of the measurements since there is no radiographic gold standard in determining static carpal alignment.

Arthroscopic assessment of the volar region of the scapholunate interosseous ligament through a volar portal.

PURPOSE: The volar region of the scapholunate interosseous ligament is one of the key structures that maintains scapholunate alignment. It is, however, difficult to evaluate this ligament using standard diagnostic procedures, including the arthroscopy through a dorsal portal. We have performed arthroscopic evaluation of this ligament through a volar portal. METHODS: Skin incision was made at just radial of the flexor carpi radialis tendon and the portal was opened through the tendon sheath. RESULTS: The volar approach enabled us to directly observe the extent of the tear of the volar region of scapholunate interosseous ligament. A shaver is inserted through the dorsal portal, and debridement can be performed by using the volar portal vein. We have not had any complications using volar portal. CONCLUSION: Volar approach is a feasible and safe procedure to evaluate and treat the volar region of the scapholunate interosseous ligament.

The Lichtman classification for Kienböck's disease: an assessment of reliability.

PURPOSE: The correct identification of Lichtman stage 3A and 3B Kienböck's disease is crucial for treatment purposes. The present study evaluates the reliability of the Lichtman classification, with specific attention to differentiating stage 3A and 3B. METHODS: Four reviewers evaluated wrist radiographs from 39 patients with Kienböck's disease. Radiographs were graded according to the traditional Lichtman classification, a modification of the Lichtman classification using a radioscaphoid angle of 60 degrees to subdivide stage 3, and 8 other radiographic measures. RESULTS: The interobserver reliability of the Lichtman classification was substantial (kappa coefficient 0.63), but Stage 3A was less reliably identified (kappa 0.38). The new modification of the Lichtman classification increased both the overall (kappa 0.81) and the stage 3A (kappa 0.75) interobserver reliability. CONCLUSION: The use of the radioscaphoid angle increases the interobserver reliability of the Lichtman classification. This should allow a better understanding of the clinically important distinction between stage 3A and 3B disease.

[Necrosis of the semilunar bone--what is possible in ambulatory operations?]. / Die Lunatum-Nekrose--was ist an ambulanten Operationen möglich?

The author has been operating on cases of lunatum necrose using all usual operating methods, excluding attached vessel pisiforme transfer, increasingly over the past 9 years without an overnight stay in hospital being necessary for patients. Depending on the quality of the structure, we have not experienced any disadvantages in comparison to hospitalised patients. Regarding funding: The costs of these operations are covered and are justifiable in combination with additional hand operations within the outpatients department.

Long-term assessment of proximal row carpectomy for chronic perilunate dislocations.

Twelve patients with chronic stage III or stage IV perilunate dislocations were managed over the past 7 years by proximal row carpectomy. All dislocations were untreated or incompletely reduced for a minimum of 8 weeks after injury. The mean time from injury to definitive treatment was 15 weeks (range, 8 weeks to 6 months). Surgical management was inclusive of a dual dorsal and volar approach. Median nerve decompression, lunate excision, and capsuloligament repair was performed volarly and scaphoid and triquetrum carpectomy was accomplished dorsally. Temporary radio capitate K-wire fixation during early soft tissue healing was uniformly performed. All patients were evaluated at an average postoperative duration of 40 months (range, 28 months to 7 years). Marked relief of wrist pain and median nerve dysesthesias was routinely achieved. Effective wrist range of motion and grip strength were restored. Untreated stage III and IV chronic perilunate dislocation treated by proximal row carpectomy eliminates pain and restores function to a severely injured wrist.

Assessment of dorsal or ventral intercalated segmental instability configurations of the wrist: reliability of sagittal MR images.

PURPOSE: To determine whether a dorsal intercalated segmental instability (DISI) or ventral intercalated segmental instability configuration can be mimicked on sagittal magnetic resonance (MR) images in asymptomatic subjects with unremarkable lateral radiographs. MATERIALS AND METHODS: In 10 asymptomatic adult volunteers, capitolunate, scapholunate, and radiolunate angles were measured on lateral radiographs and compared with those measured on T1-weighted spin-echo MR images obtained in neutrally positioned wrists with subtle variations in the sagittal imaging plane. MR measurements also were obtained in 15 degrees radially and 15 degrees ulnarly deviated wrists. RESULTS: In neutrally positioned wrists, the mean capitolunate, scapholunate, and radiolunate MR angles were 13.6 degrees-14.5 degrees, 4.0 degrees-9.9 degrees, and 18.0 degrees-20.3 degrees larger, respectively, than those on lateral radiographs. In 15 degrees radially deviated wrists, the mean MR angles were similar to those on lateral radiographs. In 15 degrees ulnarly deviated wrists, the mean MR angles were 32.3 degrees, 16.6 degrees, and 37.1 degrees larger than those on lateral radiographs. At MR imaging, a DISI configuration would have been diagnosed in four subjects with neutrally positioned wrists and in eight subjects with ulnarly deviated wrists. CONCLUSION: The lunate appears more dorsally tilted on sagittal MR images than on lateral radiographs, and a DISI configuration can be mimicked. Subtle errors in the selection of the imaging plane do not substantially influence measurements; however, wrist positioning is crucial.

Magnetic resonance imaging in the assessment of revascularization in Kienbock's disease. A preliminary report.

A 25-year-old man with stage II Kienbock's disease of his left lunate underwent an initial period of immobilization. He was subsequently treated by ulnar lengthening, with a good outcome. Magnetic resonance imaging (MRI) was utilized to demonstrate the lack of improvement with cast immobilization and the revascularization that followed surgical treatment. This new application of MRI in cases of avascular necrosis of the lunate may be helpful in the early identification of revascularization.