Rekonstruktion des distalen Radioulnargelenks mit der Herbert-Ulnakopfprothese

Objective

To provide painfree forearm rotation in patients with degenerative changes of the distal radioulnar joint (DRUJ). The primary goal is to stabilize the DRUJ in patients with an unstable stump of the distal ulna following resection arthroplasty with the secondary effect of restoring painfree forearm rotation.

Indications

Instability of the distal ulna following various types of resection arthroplasties. Primary or secondary osteoarthritis of the DRUJ. Replacement of an ulnar head destroyed by tumor or trauma.

Contraindications

Longitudinal instability of the forearm (e.g., following an Essex?CLopresti-type of injury, resection of the radial head). Inadequate soft tissue with severe ulnocarpal ligamentous insufficiency. Radial deformity (must be corrected before replacement of the ulnar head).

Surgical technique

In cases of osteoarthritis of the DRUJ, dorsal exposure of the distal radioulnar joint to the depth of the 5th extensor compartment. Raising of an ulnar-based capsuloretinacular flap by sharp dissection off the ulnar neck proximally and off the dorsal part of the triangular fibrocartilage complex (TFCC) distally. Osteotomy of the distal ulna corresponding to the preoperatively planned size of the prosthesis and removal of the ulnar head, while preserving the attachment of the TFCC within the capsuloretinacular flap. Reaming of the ulnar medullary canal. Insertion of a trial prosthesis. The trial prosthesis has to fit accurately into the shaft with a fluoroscopically documented ulna minus situation of minus 1?C2?mm at the wrist joint level. After implanting the definite stem and ulnar head of the Herbert ulnar head prothesis (Martin Medizintechnik?, Tuttlingen, Germany), the capsuloretinacular flap is reattached to the dorsal rim of the sigmoid notch through drilling holes and under advanced tension. In patients with an unstable distal ulnar stump, the operative procedure is technically more demanding as it is more difficult to raise a sufficient capsuloretinacular flap and due to the loss of the ulnar head as an anatomic landmark.

Postoperative management

Long arm cast with 70° elbow flexion, 40° forearm supination, and 20° wrist extension for 2?weeks. Subsequently forearm rotation is limited at 40° in a removable ulnar gutter splint. Six weeks postoperatively unlimited active range of motion is allowed and normal activities are gradually commenced. Return to maximum stress 12?weeks postoperatively.

Results

Patient satisfaction is high due to an increased forearm rotation, stronger grip force, and remarkable pain relief. In most patients with an unstable distal ulnar stump following resection arthroplasty of the DRUJ, stability can be restored.     

Ulnar shortening with the ulna osteotomy locking plate

Objective

Ulnar shortening for ulnocarpal unloading using a new device enabling parallel osteotomy, rotation-secured compressive shortening, lag screw placement and hybrid stabilization combined in a solely locking plate construct.

Indications

Idiopathic ulnar impaction syndrome. Posttraumatic radial shortening without major tilting of the radius in the sagittal or frontal plane, rotation deformity and/or translation of the distal fragment.

Contraindications

Advanced arthritis of the distal radioulnar joint (DRUJ), DRUJ type?III according to Tolat, malunion of the distal radius with major tilting of the radius in the sagittal or frontal plane, rotation deformity and/or translation of the distal fragment.

Surgical technique

Mounting of the UOL plate system on the palmar surface of the ulna using standard ulnopalmar exposure. Two parallel 45° osteotomies are performed using an osteotomy guide followed by rotation secured shortening and compression. Stabilization is gained by inserting an interfragmentary lag screw perpendicular to the osteotomy site and applying locking and compression screws.

Postoperative management

Lower arm cast for 4?weeks until radiological signs of bone healing become apparent. To limit negative influence of rotational forces during bone healing, patients were instructed to limit forearm rotation up to 30° in pro-/supination.

Results

Sixteen ulnar shortening osteotomies were performed in 15?patients (6?men, 9?women, average age 49?years) and evaluated retrospectively. In 10?cases a trauma-related pathology was the indication for the procedure. The average follow-up time was 53?weeks (range 12?C93?weeks). Bone union was observed at a median of 10?weeks (range 6?C33?weeks). Overall good clinical results could be achieved with an average shortening of 3.7?mm (range 2.1?C16?mm). In this series, there was one nonunion.     

Neglected epiphyseal injuries of the distal end of the radius with ulnar impaction: analysis of distal osteotomy of both bones using a dorsal midline approach

Background

To evaluate results of a technique for treating neglected epiphyseal injuries of the distal radius with ulnar impaction.

Materials and methods

This retrospective study involved six cases (four males; two females), all of whom sustained the primary injury during childhood (range 9–12 years of age). All presented with wrist deformity and ulnar-sided wrist pain. They were managed with osteotomy of the distal radius, osteotomy and shortening of the ulna, harvesting the bone grafts, and distal radioulnar joint (DRUJ) reduction performed simultaneously through a dorsal midline approach. Mean follow-up was 30 months (range 24–36).

Results

Deformity correction and pain relief was observed in all patients. Flexion arc increased from an average of 60° to 102.5°, supination from an average of 31.67° to 67.50°, and pronation from an average of 30.83° to 61.67°. The mean preoperative DASH score was 87.5, which improved to 18.72 postoperatively.

Conclusion

Neglected epiphyseal injuries of the distal radius are difficult to manage and many variations are described for handing each of the associated problems. Our technique provides an option for managing this injury with an easy surgical approach, single incision, and cost effectiveness. All the four components of the surgery, which include osteotomy of the distal radius, osteotomy of the ulna, harvesting the bone grafts, and DRUJ reduction were done through a single incision and in a single sitting. Level of evidence IV.

     

Influence of distal radioulnar joint subluxation on restricted forearm rotation after distal radius fracture

PURPOSE: To analyze the influence of subluxation of the distal radioulnar joint (DRUJ) on restricted forearm rotation after distal radius fracture. METHODS: Twenty-two cases of healed unilateral distal radial fracture with restricted forearm rotation were included in the study. The subluxation of the DRUJ was evaluated using helical computed tomography scan at neutral, maximum pronation, and maximum supination and presented as the percent displacement of the ulnar head in both the injured and uninjured sides. The radiographic parameters of palmar tilt, radial inclination, dorsal shift, radial shift, and ulnar variance were measured on plain x-ray films and the rotational deformity of the distal radius was evaluated from the computed tomography scan. The differences of each radiographic parameter from the uninjured side were calculated. The relationships between the restricted forearm rotation and the percent displacement of the ulnar head and each of the radiographic parameters were analyzed statistically. RESULTS: When forearm pronation was restricted the ulnar head was located palmarly at neutral, maximum supination, and maximum pronation with severe dorsal tilt of the distal radius. When supination was restricted the ulnar head was located dorsally at maximum supination with severe ulnar-positive variance. CONCLUSIONS: The subluxation of the DRUJ was related to restricted forearm rotation. The radiographic parameters of palmar tilt and ulnar variance showed an adverse influence on the position of the ulnar head at the DRUJ, which might lead to restricted forearm rotation after distal radial fracture.     

三角纤维软骨复合体解剖及生物力学研究

目的从解剖完整的腕关节入手,阐明三角纤维软骨复合体各组成部分的解剖特点,评估三角纤维软骨复合体(TFCC)对于维持远侧桡尺关节稳定的重要性。方法对8个新鲜解冻的腕关节和6个经甲醛浸泡的腕关节进行显微解剖。同时对影响远侧桡尺关节稳定性的因素作了初步的评估。前臂中旋位,垂直于尺骨予20N拉力下测量尺骨相对于桡骨的位移,然后先后切断掌背侧桡尺韧带,测量尺骨相对于桡骨的位移变化。结果发现掌背桡尺韧带由三角纤维软骨盘外周增厚而成,止于尺骨茎突基底部,是维持远侧桡尺关节稳定性的主要因素之一,切断掌背侧桡尺韧带会导致远侧桡尺关节明显不稳。结论TFCC由三角纤维软骨盘、掌背侧桡尺韧带、尺骨月骨韧带、尺骨三角骨韧带、尺侧腕伸肌下腱鞘、半月板同源物、尺侧囊组成。掌背桡尺韧带是维持远侧桡尺关节稳定性的主要因素之一,掌背侧桡尺韧带损伤会导致远侧桡尺关节明显不稳。     

Intra-articular distal radius fractures involving the distal radioulnar joint (DRUJ): three dimensional computed tomography-based classification

Purpose

The purpose of this study was to analyze fracture patterns and the magnitude of displacement in the distal radioulnar joint (DRUJ), by three-dimensional (3D) computed tomography (CT), for distal radius fractures with intra-articular displacement of the radiocarpal joint.

Methods

We reconstructed 3D images for 72 consecutive patients with displaced intra-articular distal radius fracture on the basis of fine-cut axial CT data. The fracture patterns involving the DRUJ were classified on the basis of the location and direction of fracture lines, and the extent of fracture comminution. We measured the maximum spatial distance of the gap and the step between the fragments in each 3D image, and the magnitudes of displacement between the groups were compared by analysis of variance followed by post-hoc analysis by use of Tukey’s test.

Results

Sixty wrists had a fracture involving the DRUJ. We classified the 60 wrists into 3 types of fracture pattern. Type 1 was a transverse fracture with minimum displacement. Type 2, in which fracture lines extended into the distal margin of the sigmoid notch, was the most common longitudinal fracture. Type 3 was a fracture with multiple fragments. The step and gap in Type 3 was significantly larger than that in the other types.

Conclusions

Eighty-three percent of intra-articular distal radius fractures had DRUJ involvement, and 28 % of the wrists had multiple fragments. For Type 3 fractures with dorsal or proximal comminution displacement was significantly larger than for simple Type 1 and 2 fractures. Surgical intervention for the DRUJ fragment may be beneficial when there is remarkable intra-articular displacement.     

Pathomechanisms of ulnar ligament lesions of the wrist in a cadaveric distal radius fracture model

Background and purpose

Mechanisms of injury to ulnar-sided ligaments (stabilizing the distal radioulnar joint and the ulna to the carpus) associated with dorsally displaced distal radius fractures are poorly described. We investigated the injury patterns in a human cadaver fracture model.

Methods

Fresh frozen human cadaver arms were used. A dorsal open-wedge osteotomy was performed in the distal radius. In 8 specimens, pressure was applied to the palm with the wrist in dorsiflexion and ulnar-sided stabilizing structures subsequently severed. Dorsal angulation was measured on digitized radiographs. In 8 other specimens, the triangular fibrocartilage complex (TFCC) was forced into rupture by axially loading the forearm with the wrist in dorsiflexion. The ulnar side was dissected and injuries were recorded.

Results

Intact ulnar soft tissues limited the dorsal angulation of the distal radius fragment to a median of 32^o (16–34). A combination of bending and shearing of the distal radius fragment was needed to create TFCC injuries. Both palmar and dorsal injuries were observed simultaneously in 6 of 8 specimens.

Interpretation

A TFCC injury can be expected when dorsal angulation of a distal radius fracture exceeds 32^o. The extensor carpi ulnaris subsheath may be a functionally integral part of the TFCC. Both dorsal and palmar structures can tear simultaneously. These findings may have implications for reconstruction of ulnar sided soft tissue injuries.A complex of ligaments on the ulnar side of the wrist supports the stability of the ulnocarpal and the distal radioulnar (DRU) joints. Included in this are the extensor carpi ulnaris (ECU) subsheath and the triangular fibrocartilage complex (TFCC), which is further subdivided into the radioulnar ligaments (RULs), the ulnotriquetral ligament (UT), and the ulnolunate (UL) ligament (Garcia-Elias 1998, Berger 2001). Injuries to the TFCC are common in dorsally angulated fractures of the distal radius fracture (Colle''s fracture) and may adversely affect functional outcome (Lindau et al. 2000). The pathomechanics of these injuries are poorly studied, however.During wrist arthroscopy, we have observed two lesions that are often present when treating TFCC lesions associated with distal radius fractures: (1) a separation of the floor of the ECU tendon sheath from the TFCC, and (2) an injury to the foveal insertion of the TFCC into the ulna. It seems probable that there must be a limit to how much the distal radius fragment can be displaced without rupture of the TFCC or fracture of the ulna.We investigated the characteristics of a TFCC injury in a cadaveric fracture model of dorsally displaced fractures. We hypothesized that (1) a TFCC lesion can be expected at a certain degree of displacement and that (2) a rupture of the foveal insertion would begin in the palmar capsule and progress dorsally, due to the dorsal displacement of the distal radius fragment.     

Long-term Outcomes of Ulnar Shortening Osteotomy for Idiopathic Ulnar Impaction Syndrome: At Least 5-Years Follow-up

Background

There have been few outcomes studies with follow-up after performing ulnar shortening osteotomy for ulnar impaction syndrome. We investigated the long-term clinical and radiological outcomes of ulnar shortening osteotomy for the treatment of idiopathic ulnar impaction syndrome.

Methods

We retrospectively reviewed 36 patients who had undergone ulnar shortening osteotomy for idiopathic ulnar impaction syndrome for a mean follow-up of 79.1 months (range, 62 to 132 months). The modified Gartland and Werley scores were measured pre- and postoperatively. The radiographic parameters for the assessment of the distal radioulnar joint (DRUJ) as well as the relationship between these radiographic parameters and the clinical and radiological outcomes were determined.

Results

The average modified Gartland and Werley wrist score improved from 65.5 ± 8.1 preoperatively to 93.4 ± 5.8 at the last follow-up visit. The average preoperative ulnar variance of 4.7 ± 2.0 mm was reduced to an average of -0.6 ± 1.4 mm postoperatively. Osteoarthritic changes of the DRUJ were first seen at 34.8 ± 11.1 months follow-up in 6 of 36 wrists (16.7%). Those who had osteoarthritic changes in the DRUJ had significantly wider preoperative ulnar variance, a longer distal radioulnar distance and a greater length of ulnar shortening, but the wrist scores of the patients who had osteoarthritic changes in the DRUJ were comparable to those who did not have osteoarthritic changes in the DRUJ.

Conclusions

The clinical outcomes are satisfactory for even more than 5 years after ulnar shortening osteotomy for treating idiopathic ulnar impaction syndrome despite the osteoarthritic changes of the DRUJ. The patients who need a larger degree of ulnar shortening may develop DRUJ arthritis.     

The dorsopalmar stability of the distal radioulnar joint

Sixteen fresh-frozen adult human cadaveric upper extremities were used in a biomechanical analysis of distal radioulnar joint (DRUJ) stability. The relative contribution to stability of the DRUJ by the surrounding anatomic structures presumed to stabilize the joint was analyzed with respect to forearm rotation and wrist flexion and extension using a purpose-built 4-axis materials testing machine. The dominant structures stabilizing the DRUJ were the ligamentous components of the triangular fibrocartilage complex proper. The major constraint to dorsal translation of the distal ulna relative to the radius is the palmar radioulnar ligament. Palmar translation of the distal ulna relative to the radius is constrained primarily by the dorsal radioulnar ligament, with secondary constraint provided by the palmar radioulnar ligament and interosseous membrane. The ulnocarpal ligaments and extensor carpi ulnaris subsheath did not contribute significantly to DRUJ stability; however, approximately 20% of DRUJ constraint is provided by the articular contact of the radius and ulna. These relationships were consistent regardless of wrist position or degree of forearm rotation.     

Die Arthrodese des distalen Radioulnargelenks mit gleichzeitiger Ellensegmentresektion nach Kapandji-Sauvé

Objective

The Kapandji-Sauvé procedure aims at improvement of rotation in the distal radioulnar joint and reduction of pain. Cases of ulnar impaction syndrome can also be corrected during the same procedure.

Indications

The most important indication is painful und restricted forearm rotation after fracture of the distal radius combined with obsolete dislocation or destruction of the distal radioulnar joint.

Contraindications

It is a salvage procedure and is contraindicated when reconstruction of the radioulnar joint or shortening of the ulna is possible. Further contraindications are rheumatic arthritis and osteoporosis.

Surgical technique

The Kapandji-Sauvé procedure creates a new distal rotatory joint due to distal radioulnar fusion and segmental resection of the distal ulna.

Postoperative management

Forearm cast including the wrist for 3?C4?weeks. Phyisiotherapy and intensive exercises of the fingers on postoperative day?1. After removing the cast, careful rotation exercises are possible.

Results

In 75?patients, the Kapandji-Sauvé procedure was performed between 1990 and 2003. Failure was observed in one patient with a bony regeneration between the resected ulnar segment. In 3 cases, a nonunion of the radioulnar joint was found. After revision with bone grafting, bony consolidation of the joint was identified in all cases. In 2 cases, there were problems with the proximal ulnar stump, whereby this was corrected in one case by resection of a ball-type callus. In the other case, painful ulna-snapping was reduced by shortening of the ulna. In earlier follow-up with 45?patients and later long-turn follow-up, ranging from 3?C12?years, not only were significant improvement of forearm rotation and reduction of pain observed, but also good patient satisfaction was found.     

Korrekturosteotomie der fehlverheilten Radiusfraktur von palmar

Background

The conservative as well as the operative treatment of distal radius fractures poses a risk of inadequate reduction or secondary dislocation. The consequences may be limited use of the hand with pain and restricted movement.

Materials and methods

Out of 21?patients with malunited fractures of the distal radius which were corrected operatively through a palmar approach, 19 have been assessed clinically as well as radiologically. The mean age was 60?years (range 45–84?years) and the mean follow-up period was 342 days. In 10 cases no autologous bone graft was inserted into the osteotomy gap.

Results

Postoperatively the average extension was 51.8° (±14.9°) and flexion 53.5° (±14°) as well as a supination of 83.8° (±11.2°) and pronation of 84.7° (±12°). The wrist score averaged 85 points, the disabilities of the arm, shoulder and hand (DASH) functional value averaged 17 points. A mean preoperative palmar inclination of ?20.9° (±10.1°) improved to 5.4° (±3.8°) after surgery and the ulnar inclination from 9° (±8.5°) to 18.1° (±6.2°).

Discussion

The correction of malunited distal radius fractures led to an improvement in function with less pain. Our data indicate that under certain circumstances interposition of an autologous bone graft does not need to be performed.     

Die arthroskopische ulnokarpale Dekompression durch Teilresektion des Ulnakopfs

Objective

Arthroscopic decompression (wafer procedure) of the ulnocarpal compartment in patients with ulnar impaction syndrome.

Indications

The arthroscopic wafer procedure is recommended in ulnar-plus situations with up to 3 mm length-excess. To perform this procedure the ulnar head needs to be accessible for the burr through a pre-existing, impaction-related, centroradial lesion of the triangular fibrocartilage complex (TFCC). The additional presence of a distal radioulnar joint (DRUJ) type C confirms the indication.

Contraindications

The wafer procedure is contraindicated if there is no consistent TFCC injury ensuring access to the ulnar head and furthermore in ulna-plus situations of more than 3 mm. Relative contraindications: in young patients due to lack of evidence-based studies.

Surgical technique

Arthroscopic, semicircular, partial resection of the ulnar head in terms of oblique–helicoidal osteotomy using a 4.2 mm burr, while sparing the DRUJ and the dorsal and the palmar radioulnar ligaments.

Postoperative management

Immobilization for 1 week in a palmar splint with immediate intensive exercising of pro- and supination under physiotherapeutic instruction.

Results

Between 2008 and 2010, an arthroscopic wafer procedure was performed in 24 patients. The resection of the ulnar head was 2.5 mm on average. After a mean follow-up time of 13.25 months, very good results were archived in 23 of 24 patients; the ulnar impingement test was negative. On a visual analog scale (0–10) average postoperative pain was 1.16 at rest and 4.5 under stress. The mean postoperative DASH score was 13.4.

     

Corrective osteotomy for malunion of distal diaphyseal/metaphyseal radius or ulna fracture affecting stability of the distal radioulnar joint

BackgroundWe postulated that residual distal radioulnar joint (DRUJ) instability after distal diaphyseal or metaphyseal fracture in the radius or ulna may occur due to malaligned or malunited bony structures as well as primary or secondary soft issue stabiliser. Here, we report the outcomes of corrective osteotomy in a retrospective study.MethodsPatients undergoing the osteotomy for DRUJ instability between March 2000 and February 2018 were included in the study. Thirteen patients were evaluated. The initial injury occurred at a mean age of 12.3 years and corrective osteotomy was performed at a mean age of 20.8 years. The mean follow-up period was 33.1 months. The male to female ratio was 8:5 and the corrected radius/ulna ratio was 11:2. DRUJ instability was diagnosed clinically and radiologically based on the stress/clunk test and the distance between the cortex of the radius, and the radioulnar ratio. All osteotomies in the radius and ulna were of the open wedge type and were performed using plates/screws.ResultsThe radioulnar ratio was significantly higher than the normal ratio (p < 0.001). All osteotomies healed well without any serious complications. The preoperative distance between the cortex of the radius and ulna was significantly decreased at the final follow-up, from 4.74 ± 0.82 to 1.16 ± 0.46 mm (p < 0.001). Positive findings of two instability tests were all converted to negative. The ranges of motion of the flexion-extension and pronation-supination arcs were significantly improved. Finally, preoperative VAS pain and DASH scores improved to 0.23 ± 0.44 and 3.92 ± 1.84, respectively (p < 0.001).ConclusionsMalunited radius or ulna plays a role in DRUJ instability, affecting the bony geometry in terms of the relationship between the sigmoid notch and ulnar head. Treatment of malunion by corrective osteotomy represents a useful option for resolving instability.Level of evidenceLevel IV, Retrospective therapeutic study.     

The distal interosseous membrane: current concepts in wrist anatomy and biomechanics

The distal interosseous membrane (DIOM) of the forearm acts as a secondary stabilizer of the distal radioulnar joint (DRUJ) when the dorsal and palmar radioulnar ligaments of the triangular fibrocartilage complex are cut. Recent anatomical studies revealed that thickness of the DIOM varies widely among specimens and the distal oblique bundle (DOB) exists within the DIOM in 40% of specimens. The DOB originates from the distal one-sixth of the ulnar shaft and runs distally to insert on the inferior rim of the sigmoid notch of the radius. The mean thickness of the DIOM without a DOB was 0.4 mm, which was significantly thinner than 1.2 mm with a DOB. Biomechanical studies have shown that the DOB is an isometric stabilizer of the forearm during pronosupination. The presence of a DOB was shown to have a significant impact on DRUJ stability. Innate DRUJ laxity in the neutral forearm position was greater in the group without a DOB than in the group with a DOB. Ulnar shortening with the osteotomy performed proximal to the attachment of the DIOM had a more favorable effect on stability of the DRUJ compared with the effect of distal osteotomy, especially in the presence of a DOB. The longitudinal resistance to ulnar shortening was significantly greater in proximal shortening than in distal shortening. It also suggested that the DIOM is of great importance in the management of concomitant ulnar-side injuries in distal radius fracture.     

Patterns of subchondral bone mineralization in the distal radioulnar joint

PURPOSE: Studies have shown that it is possible to derive direct knowledge about the actual mechanical conditions of the wrist by analyzing the subchondral mineralization. The aim of the present study was to evaluate the distribution of the subchondral bone mineralization of the distal radioulnar joint (DRUJ) noninvasively in living subjects by using computed tomography (CT) osteoabsorptiometry to gain new information about the long-term loading conditions. METHODS: Twenty-two wrist joints were investigated in 11 healthy young subjects by means of CT osteoabsorptiometry. The CT scans of the DRUJ were taken in the axial plane in neutral position of the forearm and in both maximum pronation and supination. The CT datasets of 1.5-mm sections were obtained and then transferred to an image-analyzing system. The subchondral bone plate in each section was isolated, reconstructed in 3 dimensions, and converted into a false color series. RESULTS: The maximum subchondral bone density in the sigmoid notch of the radius was found along the distal border in all wrists. It was located dorsally in 10 wrists, palmarly in 8 wrists, and centrally in 4 wrists. The maximum bone density on the corresponding articular surface of the ulna was found dorsally in 10 cases, centrally in 8 cases, and palmarly in 4 cases. In 13 cases the maximum bone density was found in direct opposition on radius and ulna in neutral position. A statistically significant difference could not be detected in subjects with an ulna minus variance nor in those with a DRUJ angulation greater than 10 degrees . CONCLUSIONS: Our results show that in the sigmoid notch the load is transmitted through either the dorsal or palmar parts of the joint. In contrast the maximum bone density on the side of the ulna was found dorsally and centrally. We conclude that the ulna receives the maximum load in neutral position and supination, whereas because of the dorsopalmar translation of the ulnar head the radius may lead the ulna with either its palmar or dorsal borders during pronosupination. The ligamentous apparatus, the shape of the joint, and the ulna variance, however, may influence load transmission.     

Modified brachioradialis wrap for stabilizing the distal radioulnar joint: case report

Distal radioulnar joint (DRUJ) stability requires competent static and dynamic soft tissues. Multiple DRUJ techniques have been described in the literature. Our method is a novel modification of the Gupta method of DRUJ stabilization used in a revision reconstruction on a patient with a total wrist arthroplasty. A brachioradialis graft is harvested and tunneled through Parona’s space volar to the pronator quadratus and through the muscle body. The tendon is then brought dorsal between the radius and ulna to the dorsal side of the distal ulna and sutured to the floor of the 5th extensor compartment, as well as to the surrounding extensor reticulum ulnar to the 6th compartment with nonabsorbable sutures. Our modification of the method described by Gupta prevents ulnar subluxaton of the extensor carpal ulnaris (ECU), allows the tendon graft construct to more adequately resist volar translation of the radius, and thus acts like a leash to pull the radius dorsally to the stationary ulna. This modification gives the graft a better force vector to resist the volar translation of the distal radius. We are able to present successful 30-month follow-up of this procedure.

Electronic supplementary material

The online version of this article (doi:10.1007/s11552-015-9752-0) contains supplementary material, which is available to authorized users.     

Irreducible chronic palmar dislocation of the distal radioulnar joint--a case report.

We report a rare case of irreducible chronic palmar dislocation of the distal radioulnar joint (DRUJ). This case showed that the dislocated ulnar head was impacted to the palmar cortex of the radius probably due to the dynamic force of the pronator quadratus muscle. Re-attachment of the ulnar styloid and partial resection of the ulnar head were necessary to make the reduction of the DRUJ possible. The continuity of the radioulnar ligament to the ulnar head was restored and the stability of DRUJ was maintained after reduction.     

Kinematics of the distal radioulnar joint

The kinematics of the normal distal radioulnar joint (DRUJ) in five fresh frozen cadavers were investigated by means of computerized tomography (CT). Rotation of the radius about the ulna is accompanied by translation so that in supination the ulna is somewhat palmar, and in pronation the ulna is more dorsal relative to the radius. The average ranges of motion of the hand and DRUJ were 260 degrees and 190 degrees, respectively. Significant carpal and metacarpal rotation occurred with pronation-supination of the hand. The DRUJ has both rotational and translational components of movement and does not have a single center of rotation. The pathway of the instantaneous centers of rotation, or centrode, of the DRUJ has a characteristic pattern. The centrode moves in a direction opposite that of the DRUJ movement and is located near the center of the ulnar head. A prosthetic joint for the DRUJ should not have a fixed axis of rotation but should allow the normal translatory motion of the ulna and radius if early joint failure is to be prevented.     

Volar locking plate fixation of distal radius fractures: use of an intra-operative ‘carpal shoot through’ view to identify dorsal compartment and distal radioulnar joint screw penetration

Introduction

We report our experience using a ‘carpal shoot through’ view of the distal radius to identify dorsal compartment screw penetration intra-operatively when performing volar plating of the distal radius.

Methods

A prospective study of 42 patients (mean age 56 years) with acute distal radius fractures treated with open reduction internal fixation was undertaken. Surgical fixation was performed using a volar locking plate in all patients. After plate application, inclined posteroanterior and lateral radiographs were taken followed by the carpal shoot through view.

Results

In six cases (14 %), the carpal shoot through view revealed dorsal screw protrusion, which was not detectable on standard PA and lateral views. In one case, a screw had penetrated the distal radioulnar joint (DRUJ), which was only apparent on the shoot through view. The overall screw exchange rate was 17 %.

Conclusions

Using the hand and carpus to minimise the contrast in X-ray penetration, the dorsal cortex of the distal radius may be imaged intra-operatively and dorsal compartment screw penetration detected in cases with significant multifragmentation when screw measurement is difficult. This view potentially reduces the risk of post-operative pain and extensor tendon injury and also provides excellent visualisation of the DRUJ.     

Erste Ergebnisse der multidirektional-winkelstabilen palmaren Osteosynthese der distalen Radiusfraktur

Background

The management of fractures of the distal radius continues to evolve. New operative strategies have recently been developed including the use of fixed-angle plates. This study reviews the results of 20 patients with fractures of the distal radius treated with a new multidirectional fixed angle plate.

Method and materials

A total of 20 patients with closed Colles type fractures of the distal radius were treated with Medartis (Aptus 2.5) palmar fixed-angle plates. Surgery was performed under plexus anesthesia using the standard or extended flexor carpi radialis (FCR) approach. Patients were evaluated prospectively with a mean follow-up of 26 weeks (range 23–28 weeks). Pain, range of motion, grip strength, DASH score, modified Mayo wrist score and radiographs were obtained. The level of significance was set at 95% and the χ² and ANOVA tests in combination with a post hoc Tukey test were used for statistical analysis.

Results

The average range of motion (ROM) in extension-flexion was 87° (76% of the contralateral side) and in ulnar-radial deviation 42° (88% of the contralateral side). Pain values (visual analogue scale 0–100) at follow-up were 3 (without stress) and 24 (with stress). Grip strength improved to 84% of the contralateral side, the mean DASH score was 13 points and the modified Mayo wrist score confirmed the excellent results with a mean value of 83±27 points. Radiological examination showed a satisfactory result with an ulna variance of 0.9±0.4 mm, radio-ulnar inclination of 21±5° and palmar inclination of 4±6°.

Conclusions

Our data show that treating unstable distal radius fractures with multidirectional palmar fixed-angle plates is reliable and effective and produces good early functional and radiological results. However, long-term results with a larger number of patients and randomized prospective studies comparing this technique with other established procedures are required.