Radiotriquetral Ligament Research Articles

Assessment of 3.0 Tesla magnetic resonance imaging in Madelung’s deformity: findings and implications

ObjectiveThe aim of the study was to investigate the 3.0 Tesla magnetic resonance imaging (MRI) features of Madelung’s deformity.Materials and methodsThe wrist MRI scans of 19 patients clinically diagnosed with Madelung’s deformity and 20 patients without deformity were consecutively selected from Beijing Jishuitan Hospital between April 2019 and December 2022 for observation, in the case group and control group, respectively. Multiple linear regression was used to analyze the factors affecting tilting angle and width of central disc (CD, also termed as triangular fibrocartilage, the main component of triangular fibrocartilage complex), while the chi-square test was used to compare the occurrences of CD (radial) attachment displacement, VL, and RTL. p < 0.05 indicated statistical significance.ResultsMadelung’s deformity significantly contributed to the tilting and thickening of the CD. In the case group, the tilting angle and thickness of CD were (51.46 ± 1.33)° and (0.23 ± 0.01) cm, respectively, which was statistically significant (p < 0.05); the radial attachment of the CD significantly shifted away from the distal articular surface level (χ2 = 39.00, p < 0.001), with a mean displacement of (0.97 ± 0.38) cm. Furthermore, the cases demonstrated abnormally developed Vickers ligament (χ2 = 35.19, p < 0.001) and radiotriquetral ligament (χ2 = 25.66, p < 0.001).ConclusionMRI provides a notable advantage in diagnosing Madelung’s deformity. Compared with the control group, patients with Madelung's deformity exhibited tilting and thickening of the CD. Additionally, the radial attachment of the CD was significantly shifted proximally with abnormal development of Vickers and radiotriquetral ligaments.

Modified Brunelli Reconstruction for Scapholunate Ligament Dissociation.

The present video article describes the steps, alternatives, and outcomes of the modified Brunelli reconstruction, also known as 3-ligament tenodesis, for the treatment of irreparable scapholunate dissociations. The presently described technique is generally utilized in cases in which there is an irreparable disruption of the scapholunate ligament and widening of the scapholunate junction with no carpal arthritis. Other treatment options for irreparable scapholunate dissociation include various forms of capsulotenodesis, bone-ligament-bone reconstruction, tendon-based reconstructions, partial wrist arthrodesis, and proximal row carpectomy. The modified Brunelli reconstruction is indicated for a nonrepairable complete scapholunate ligament injury with a reducible rotatory subluxation of the scaphoid, without cartilage degeneration. The dorsal scapholunate ligament is reconstructed and the distal palmar scaphoid rotation is corrected with use of a distally based flexor carpi radialis tendon. The reconstruction is achieved by placing the flexor carpi radialis tendon through a transosseous scaphoid tunnel and weaving the tendon through the dorsal ulnar capsule or radiotriquetral ligament. The modified Brunelli technique has been shown to restore wrist motion to 70% to 80% of that of the contralateral wrist and grip strength to 65% to 75% of that of the contralateral wrist, as well as to provide good pain relief in approximately 70% to 80% of patients. With use of simple instrumentation, C-arm fluoroscopy, and proper surgical technique, this operative procedure is fairly reproducible. FCR = flexor carpi radialisK-wire = Kirschner wire.

Sonographic Findings in Adult Congenital Madelung Deformity: A Case Study

This case study describes six sonographic findings, with correlative imaging, in an adult patient with congenital Madelung deformity. Two are typical of congenital Madelung deformity: a thick volar hyperechoic band extending from the ulnar side of the distal radius toward the lunate-triquetrum area, the so-called Vickers ligament, adjacent to the radiotriquetral ligament, and a cortical defect on the ulnar and volar side of the distal radius. Other findings may be also observed, such as a narrowed distance between the Lister tubercle and the distal radioulnar joint, a dorsal subluxation of the ulnar head, an extensor tendons entrapment and pronator quadratus modifications. Although the diagnosis of congenital Madelung deformity is based usually on clinical examination, this rare malformation may remain undiscovered until adulthood. When sonography is used as the first imaging technique, the sonographic findings of congenital Madelung deformity can facilitate diagnosis and the appropriate radiographs.

MRI appearance of the anomalous volar radiotriquetral ligament in true Madelung deformity

To characterize the MRI appearance of the anomalous volar radiotriquetral ligament in cases of classic Madelung deformity. With institutional review board approval, a search of the radiology information system was performed to identify cases of potential Madelung deformity using variations of the criteria "Madelung deformity." Cases of classic Madelung deformity were included based on the following criteria: dorsal subluxation of the ulnar head, volar tilt of the distal radius, increased radial inclination of greater than 25°, triangulation of the carpus, and presence of Vickers ligament defined as an anomalous volar radiolunate ligament. Patients with a history of wrist trauma or severe degenerative change distorting anatomy were excluded. The resulting cases were reviewed to characterize the anomalous radiotriquetral ligament. Eight cases of classic Madelung deformity in 6 patients were identified. All 8 cases were characterized by the presence of an anomalous radiotriquetral ligament, which was more conspicuous than Vickers ligament. None of the excluded pseudo-Madelung deformity cases displayed a Vickers ligament or radiotriquetral ligament. The radiotriquetral ligament is an anomalous ligament that is a constant and distinguishing finding in classic Madelung deformity in this study. Awareness of the radiotriquetral ligament and distinguishing it from Vickers ligament on imaging studies and at surgery may have clinical implications that need to be further investigated.

Arthroscopic Ligament Plication for Palmar Midcarpal Instability

Introduction Palmar midcarpal instability (PMCI) is a painful condition characterized by a kinematic dysfunction of the proximal carpal row (PCR). Although its etiology is still poorly understood, it is believed to be due to congenital (or traumatic) laxity of the ligaments that stabilize the PCR, primarily, the dorsal radiotriquetral (DRT) ligament and the ulnar arm of the palmar arcuate ligament. This laxity causes an unphysiologic coupling of the midcarpal joint, which is clinically evident as a painful clunk with ulnar wrist deviation. Most symptomatic PMCI patients benefit from nonoperative management, which is based on splinting and proprioceptive neuromuscular rehabilitation. However, patients that do not respond to nonoperative management are candidates for surgical treatment. Cases with mild to moderate symptoms may be treated with soft tissue procedures, such as dorsal capsular reefing (Lichtman, 2006) or arthroscopic shrinkage (Mason, 2007; Lichtman, 2003). The purpose of this study was to present our results with a personal technique of arthroscopic ligament plication (ALP) for PMCI.

Load transfer through the radiocarpal joint and the effects of partial wrist arthrodesis on carpal bone behaviour: a finite element study

A finite element model of the wrist was developed to simulate mechanical changes that occur after surgery of the wrist. After partial arthrodesis, the wrist will experience altered force transmission during loading. Three different types of partial arthrodesis were investigated - radiolunate, radioscaphoid, and radioscapholunate - and compared with the healthy untreated wrist. The results showed that the compressive forces on the radiocarpal joint decreased compared with the untreated wrist with both radiolunate and radioscaphoid fusions. The load transmission through the midcarpal joints varied depending on arthrodesis type. The forces in the extrinsic ligaments decreased with the fusion, most noticeably in the dorsal radiotriquetral ligament, but increased in the dorsal scaphotriquetral ligament. From the results of the study it can be concluded that the radioscapholunate fusion shows the most biomechanically similar behaviour out of the three fusion types compared with the healthy wrist. The modelling described in this paper may be a useful approach to pre-operative planning in wrist surgery.

The Mechanism of Ulnar-sided Perilunate Instability of the Wrist: A Cadaveric Study and 6 Clinical Cases

To define the mechanism of ulnar-sided perilunate instability using a cadaveric model and correlate these biomechanical findings with 6 clinical cases. We mounted 16 fresh-frozen human cadaver arms and loaded them to failure in extension and radial deviation, recreating our understanding of the injury mechanism leading to ulnar-sided perilunate instability of the wrist. After testing, we examined the wrists clinically and radiographically. We identified, examined, and treated 6 patients with ulnar-sided perilunate instability over a period of 5 years. Based on these data, we propose a 3-stage mechanism for ulnar-sided perilunate instability of the wrist. In 13 of 16 specimens, we observed failure of ulnotriquetral, ulnolunate, and ulnocapitate ligaments as well as the dorsal scaphotriquetral and dorsal radiotriquetral ligaments. In 11 of these 13, the lunotriquetral interosseous ligament was disrupted, and in 2 of the 11, a dorsal perilunate dislocation occurred. After comparing these laboratory findings with clinical findings in 6 patients with ulnar-sided perilunate instability, we propose the following 3-stage mechanism for ulnar-sided perilunate instability: stage 1, disruption of the lunotriquetral interosseous ligament; stage 2, stage 1 plus disruption of the ulnolunate, ulnotriquetral, and ulnocapitate ligaments as well as the dorsal scaphotriquetral and radiotriquetral ligaments; and stage 3, stage 2 with progression of the injury through the midcarpal joint plus disruption of the scapholunate and radioscapholunate ligaments, potentially resulting in a dorsal perilunate dislocation. We describe a 3-stage mechanism of ulnar-sided perilunate ligamentous wrist injury that can lead to dorsal perilunate dislocation. We recommend considering ulnar-sided perilunate instability of the wrist in patients with ulnar wrist pain after a fall on the outstretched wrist. Ulnar-sided wrist injury can lead to subtle forms of perilunate instability.

High-resolution ultrasound evaluation of extrinsic wrist ligaments in patients affected by rheumatoid arthritis

To evaluate the ultrasound features of the extrinsic wrist ligaments in rheumatoid arthritis (RA) patients in comparison with healthy volunteers. Twenty-one consecutive patients affected by RA (12 men, 9 women; mean age 57 ± 14.6years) were compared with 21 controls (12, 9; 54 ± 12.1, respectively). Wrists were evaluated using ultrasound on both palmar and dorsal sides along each ligament, using carpal bones as references. The following ligaments were studied: radioscaphocapitate, radiolunotriquetral, palmar ulnolunate, palmar ulnotriquetral, dorsal radiotriquetral, dorsal ulnotriquetral, and radial collateral ligament. Ligament number and thickness were noted. Echotexture was rated as fibrillar, fragmented, or heterogeneous; the surface was rated as smooth or blurred. The number of palmar ulnolunate and palmar ulnotriquetral ligaments detected by ultrasound in patients was significantly lower than in controls (P = 0.031 and P = 0.037, respectively). All ligaments had significantly more fragmented or heterogeneous echotexture and blurred surface and were significantly thinner in patients than in controls (P < 0.001). No correlation was found between ligament thickness and RA duration or clinical parameters. Extrinsic wrist ligaments were less detectable and thinner in patients affected by RA compared with healthy volunteers matched for age and sex. Ligament thinning did not directly correlate with RA duration and clinical parameters. • Ultrasound is increasingly used to evaluate normal anatomy of extrinsic wrist ligaments. • Extrinsic wrist ligaments are thinner in rheumatoid arthritis patients than in controls. • Extrinsic wrist ligaments are less easy to detect in rheumatoid arthritis patients. • Ligament thinning and detectability are not related to clinical parameters.

In Brief: Mayfield et al. Classification: Carpal Dislocations and Progressive Perilunar Instability

According to Melsom and Leslie, the earliest description of perilunate dislocation was by Malgaigne in 1855, before the advent of radiography [7]. It later was described by Cousins, Destot, de Quervain, and others [7]. According to Melsom and Leslie [7] Tavernier reported the first series in 1906. Many years later, in 1968, the concept of the proximal row as an intercalated segment was described by Fisk [7]. In 1972, Linscheid et al. [4] modified the concept to develop models of dorsal and volar intercalated instability. The ligamentous pathoanatomy and classification of these injuries, however, had not been well described. In 1980, Mayfield et al. [5] performed a cadaveric study to better delineate the pathoanatomy and classify the degree of carpal instability after perilunate injury. Purpose

Midcarpal instability: a radiological perspective

Midcarpal instability (MCI) is the result of complex abnormal carpal motion at the midcarpal joint of the wrist. It is a form of non-dissociative carpal instability (CIND) and can be caused by various combinations of extrinsic ligament injuries that then result in one of several subtypes of MCI. The complex patterns of injury and the kinematics are further complicated by competing theories, terminology and classifications of MCI. Palmar, dorsal, ulna midcarpal instability, and capitolunate or chronic capitolunate instability are all descriptions of types of MCI with often overlapping features. Palmar midcarpal instability (PMCI) is the most commonly reported type of MCI. It has been described as resulting from deficiencies in the ulna limb of the palmar arcuate ligament (triquetrohamate-capitate) or the dorsal radiotriquetral ligaments, or both. Unstable carpal articulations can be treated with limited carpal arthrodesis or the ligamentous defects can be treated with capsulorrhaphy or ligament reconstruction. Conventional radiographic abnormalities are usually limited to volar intercalated segment instability (VISI) patterns of carpal alignment and are not specific. For many years stress view radiographs and videofluoroscopy have been the methods of choice for demonstrating carpal instability and abnormal carpal kinematics respectively. Dynamic US can be also used to demonstrate midcarpal dyskinesia including the characteristic triquetral "catch-up" clunk. Tears of the extrinsic ligaments can be demonstrated with MR arthrography, and probably with CT arthrography, but intact yet redundant ligaments are more difficult to identify. The exact role of these investigations in the diagnosis, categorisation and management of midcarpal instability has yet to be determined.

Die Fesselung des Kahnbeins nach Brunelli in der Modifikation nach Garcia-Elias, Lluch und Stanley zur Behandlung der veralteten skapholunären Dissoziation

Stabilization of the scaphoid correcting rotary subluxation and replacement of the biomechanically essential dorsal part of the scapholunate ligament for prevention of osteoarthritis. Scapholunate dissociation without useful remnants of the ligament and reducible malalignment of the scaphoid. Fixed scaphoid malalignment. Osteoarthritis (SLAC [scapholunate advanced collapse] wrist). Dorsal approach to the wrist using the flap described by Berger. Correction of rotary subluxation and stabilization of the scaphoid using a distally based strip of flexor carpi radialis tendon, which is created through a separate palmar incision, and fixed to a bone anchor in the lunate through a tunnel from the palmar side of the distal pole of the scaphoid to the origin of the dorsal part of the scapholunate ligament from the scaphoid combined with transfixation of the scaphoid to the capitate and the lunate bone in corrected position using two Kirschner wires (1.6 mm). Additionally, the flexor carpi radialis strip is looped through a split in the dorsal radiotriquetral ligament and fixed to itself. Immobilization using a below-elbow cast including the metacarpophalangeal joint of the thumb for 6 weeks. Removal of the Kirschner wires 8 weeks postoperatively, followed by physiotherapy to improve wrist motion. 14 out of 17 patients were available for a clinical and radiologic examination after a mean follow-up time of 10.5 months (minimum 6, maximum 15 months). Two of these patients had to undergo another operative procedure in the meantime, one partial and the other total wrist fusion. The remaining twelve patients had a mean DASH Score (Disabilities of the Arm, Shoulder and Hand) of 25 (minimum 0, maximum 59 points) and a mean modified Mayo Wrist Score of 80 points (minimum 60, maximum 97 points). Contrary to the good clinical results, the final radiologic examination demonstrated a tendency toward loss of correction compared to the postoperative X-rays.

Dorsal Capsulodesis for the Treatment of Scapholunate Instability

To regain stability of the proximal carpal row after scapholunate ligament rupture in order to avoid osteoarthritis and carpal collapse. As additional therapy in scapholunate ligament repair especially in patients with static, but reducible scapholunate malalignment. Fixed scapholunate malalignment. Osteoarthritis of the radiocarpal or the midcarpal joint. Dorsal approach to the carpal joint with release of the second, third and fourth extensor compartment and resection of the dorsal interosseous nerve. Opening of the radiocarpal joint for inspection of the chondral surfaces and the scapholunate ligament for possible repair. If needed, reduction of scaphoid and lunate. Repair of the scapholunate ligament. If a reduction of scaphoid and lunate is necessary, temporary Kirschner wire fixation of the scaphoid to the capitate and the lunate. The dorsal intercarpal ligament is identified and its middle third is dissected and elevated from the triquetrum remaining attached to the distal scaphoid pole. The ulnar end of the elevated part of the dorsal intercarpal ligament is pulled through a split in the dorsal radiotriquetral ligament and fixed to itself. Closure of the proximal and distal third of the dorsal intercarpal ligament. Management Immobilization in a below-elbow cast including the metacarpophalangeal joint of the thumb for 6 weeks. Removal of the Kirschner wires, if used, 8 weeks postoperatively. Physiotherapy to improve wrist motion. Most of the reports in the literature show an improvement of pain. The effect on radiologic parameters and the development of osteoarthritis remains uncertain.

Long-term results of lunocapitate arthrodesis with scaphoid excision for SLAC and SNAC wrists

When treating the degenerative arthritis that follows scapholunate instability or scaphoid pseudarthrosis, excision of the scaphoid must be combined with a stabilisation of the midcarpal joint. Two alternatives have been proposed for that purpose: fusing the lunate, triquetrum, capitate and hamate (four corner fusion), 4CF; or limiting the arthrodesis to the lunate and capitate, preserving or excising the triquetrum. Previous reports have attributed a high level of complications to lunocapitate arthrodesis, mainly in respect of nonunion. We have reviewed 17 patients who had been treated with a lunocapitate fusion, after an 8 to 12-year follow-up period, and found similar results compared with 4CF, even with a major degree of motion in ulnar-radial deviation. Recent work on the innervation of the radiotriquetral ligaments has given relevance to the preservation of lunotriquetral motion in maintaining proprioception. Also if the triquetrum is excised to gain more motion, the proprioceptive role of the radiotriquetral ligaments is compromised.

High resolution 3.0 Tesla MR imaging findings in patients with bilateral Madelung’s deformity

Madelung deformity (MD) is a rare, normally painful abnormality of the wrist and forearm which characteristically begins in adolescence. Usually the deformity appears between the age of 8 and 14 years, often progressing from initially mild functional pain to fatigue and loss of strength and finally, reduced mobility. We present the MR-findings in three patients with bilateral MD, using a high-resolution imaging protocol adapted for 3.0 Tesla (3.0 T) examinations. Wrist images of three patients were acquired at a 3.0 T Scanner (Gyroscan Intera, Philips Medical Systems, Best, The Netherlands), using a dedicated phased array coil. The imaging protocol consisted of coronal T1-weighted Turbo-spin-echo (T1w-TSE) and coronal and sagittal T2-weighted TSE sequences (T2w-TSE). MR-images of these three girls demonstrated severe volar bayonet configuration of the forearms with a dorsal prominence of the ulnar head, also a curved distal radial articular surface with increased ulnar angulation, due to a deceleration of growth in the ulnar portion of the distal epiphysis. The proximal carpal row showed pyramidal configuration. Also visible was a prominent short radiolunate ligament, the so called Vickers ligament, which originates from the ulnar border of the radius, inserts into the volar pole of the lunate and likely contributes to carpal pyramidalization. Furthermore, the images demonstrated an anomalous hypertrophied and elongated volar radiotriquetral ligament which, to our knowledge, has been described elsewhere only in another case. High resolution imaging at 3.0 T permitted a detailed analysis of the complex pathomorphology in patients with MD. Investing the better signal-to-noise ratio at higher field strengths into spatial resolution an excellent image quality could be obtained, depicting the Vickers ligament and the anomalous volar radiotriquetral ligament in this rare disease.

Ultrasonographic evaluation of normal extrinsic and intrinsic carpal ligaments: preliminary experience

To determine normal anatomy of extrinsic and intrinsic carpal ligaments at ultrasonography (US). In the first part of the study, two musculoskeletal radiologists retrospectively reviewed in consensus the photographs of anatomic sections and dissections derived from 20 cadaveric wrists. This cadaveric study gave the two readers the opportunity to learn the anatomy and orientation of the various extrinsic and intrinsic carpal ligaments and, thus, to develop a US protocol to facilitate the recognition of each carpal ligament. In the second part of the study, these two radiologists prospectively and independently evaluated the visibility of extrinsic and intrinsic carpal ligaments in 30 wrists of volunteers, using the same US protocol. With regard to extrinsic carpal ligaments, the radioscaphocapitate ligament (partially visible, 38%; completely visible, 62%), the radiolunotriquetral ligament (partially visible, 27%; completely visible, 73%), the palmar ulnotriquetral ligament (partially visible, 12%; completely visible, 88%), and the dorsal radiotriquetral ligament (partially visible, 7%; completely visible, 93%) were visualized at US. The dorsal ulnotriquetral ligament (partially visible, 21%; completely visible, 74%), the ulnolunate ligament (partially visible, 5%; completely visible, 70%), and the radial collateral ligament (partially visible, 18%; completely visible, 12%) were more difficult to recognize. The radioscapholunate ligament was never seen. With regard to intrinsic carpal ligaments, the dorsal (partially visible, 11%; completely visible, 89%) and palmar (partially visible, 38%; completely visible, 62%) scaphotriquetral ligaments as well as the dorsal scapholunate ligament (partially visible, 3%; completely visible, 97%) were visualized at US. The dorsal lunotriquetral ligament (partially visible, 39%; completely visible, 61%) and the palmar scapholunate ligaments (partially visible, 12%; completely visible, 81%) were more difficult to recognize. US may be helpful in identifying the major extrinsic and intrinsic carpal ligaments.

Die radiokarpale Luxationsfraktur

Radiocarpal fracture dislocation is a very rare, often complex injury and the result of high energy trauma. We present a retrospective review of four patients. The injury in our series was characterized by a complete dorsal dislocation of the radiocarpal joint with fracture of the radial styloid, associated with avulsion of the palmar and dorsal cortical margin of the distal radius (radiotriquetral ligament included). One case presented a die punch fracture, another case a partial lesion of the scapholunate ligament. All injuries were immediately treated by closed reduction in local anaesthesia. All patients underwent operative treatment with a dorsal approach within seven days. The radial styloid was fixed with screws or Kirschner-wire, the impaction of the dorsoulnar aspect of the radius with elevation and fixation with a 2.7 mm plate. The tear of the scapholunate ligament was sutured and stabilized with Kirschner-wire between scaphoid and lunatum. All wrists were immobilized with a forearm cast for four weeks. The mean follow-up was 25 months. At the time of follow-up all patients showed a very good functional outcome, although the radiographic analysis revealed some osteoarthrotic changes.

Occult scapholunate ganglion: a cause of dorsal radial wrist pain.

There are multiple causes for chronic dorsal wrist pain over the scapholunate ligament, including occult dorsal carpal ganglion cyst, scaphoid impaction syndrome, dorsal carpal capsulitis, distal posterior interosseous nerve syndrome, and dynamic scapholunate ligament instability. Patients with such pain often have normal x-rays. A retrospective study of 21 patients undergoing surgical exploration for chronic dorsal radial wrist pain who had no palpable cyst and normal x-rays revealed that 18 of the patients had occult scapholunate ganglion cysts or myxomatous degeneration within the scapholunate ligament. All had failed long-term conservative management. Surgery involved an approach through Langer's lines, resection of a large triangular portion of the capsule between the dorsal intercarpal and radiotriquetral ligaments, and tangential debridement of the area of myxoid degeneration proximal to the distal 2 to 3 mm of dorsal scapholunate interosseous ligament. None of the patients had scapholunate instability or scaphoid impacting syndrome. Of the 18 patients with histologically confirmed myxomatous changes in the scapholunate ligament, 16 had an excellent outcome as defined by rigorous criteria; 1 had a good outcome. There was 1 patient with a poor result. A compelling argument is made for surgical exploration of the scapholunate joint in patients with persistent dorsal radial wrist pain and scapholunate point tenderness.

Wrist ligament strain during external fixation: a cadaveric study.

The purpose of this study was to evaluate the change in strain (elongation) that occurs in 2 extrinsic ligaments of the wrist (volar radioscaphocapitate and dorsal radiotriquetral) as the wrist is sequentially distracted with an external fixator. Six fresh cadaver specimens were dissected to expose the dorsal radiotriquetral and volar radioscaphocapitate ligaments. A differential variable reluctance transducer strain gauge was applied to both ligaments and the wrist was serially distracted in increments of 5 mm with an Agee WristJack (Hand Biomechanics Laboratory, Sacramento, CA). The distraction increments were measured on the WristJack. X-rays were obtained at each level of distraction. At 10 mm of WristJack distraction, the strain in both the volar radioscaphocapitate and dorsal radiotriquetral ligaments increased to greater than 20%. An increase to a 0.63 carpal height index resulted in an increase in strain of 20%. This increased strain may contribute to wrist stiffness.

A new method for measuring wrist-joint ligament length changes during sagittal and frontal motion

Objective. The present study addresses elongation patterns of selected capsular wrist ligaments during two types of planar wrist motion. Design. In vitro continuous measurement of capsular ligament elongation using miniature cisplacement transducers. Background. The function of the capsular wrist ligaments in carpal kinematics is still to be determined unambiguously. Most previous studies on carpal ligament behaviour were realised using X-ray stereophotogrammetric methods. Methods. Elongation of the palmar radiolunate, radiocapitate and ulnocapitate ligaments, as well as of the dorsal radiotriquetral ligament during frontal and sagittal wrist motion were analysed in 10 anatomical specimens using miniature differential variable reluctance transducers. Wrist motion was tracked using a six-degree-of-freedom electrogoniometer. Results and conclusions. In most instances, the elongation of these ligaments was similar for two motion modalities tested (guided by a rail or free) with, however, a trend to larger individual variations and smaller elongation during free motion for several ligaments. The capsular ligaments considered in this study displayed length changes inferior to 15% of the initial length. The individual elongation patterns and ranges were highly variable, contrasting with excellent intra-individual reproducibility. Relevance This study presents a method for continuous tracking of in vitro ligament elongation patterns liable to provide new features if applied after simulation of wrist disorders. Besides morphologic and kinematic variations shown previously, the wrist seems to display variations in ligament length changes, which could partially explain the variability of carpal bone motion, although further studies are needed to determine the influence of their variations on carpal kinematics.

Madelung deformity in skeletally immature patients: morphologic assessment using radiography, CT, and MRI.

The purpose of this study was to define the pathoanatomy of the distal radius and surrounding soft tissues, identify the factors that may contribute to diminished forearm rotation, and relate these findings to alterations in wrist motion in skeletally immature patients with the Madelung deformity. Four skeletally immature female patients with bilateral Madelung deformities (eight wrists) underwent evaluation of each wrist with radiography, CT, and MRI to assess the morphology of the deformity. Two patients (four wrists) had isolated idiopathic Madelung deformities, and two patients (four wrists) had Madelung deformities secondary to dyschondrosteosis. Radiographically, all wrists demonstrated dorsal bowing of the radius, marked ulnar tilting of the radius and radial tilting of the ulna, volar tilting of the distal articular surface of the radius, and triangulation of the epiphysis. On CT, patients with the idiopathic deformity demonstrated dorsal ulnar subluxation and relative supination of the carpus with respect to the distal radius. Patients with dyschondrosteosis demonstrated no ulnar subluxation and relative pronation of the carpus. All wrists demonstrated a fixed pronated deformity of the distal radius. On MRI, a physeal bar that bridged the distal metaphysis of the radius to the epiphysis was identified in all eight wrists, located on the volar aspect of the radius at the lunate facet. An anomalous volar ligament, a volar radiotriquetral ligament, and the short radiolunate ligament were hypertrophied in seven wrists. Based on its location, it is likely that a physeal bar impedes the normal development of the distal radius ulnarly. Hypertrophy of the short radiolunate ligament may be an important contributing factor to carpal pyramidalization owing to tethering on the volar pole of the lunate. Diminished forearm rotation is likely related to carpal malalignment, a fixed pronated deformity of the distal radius, and dorsal bowing of the radius.