Radial head fractures and their effect on the distal radioulnar joint. A rationale for treatment.

Nineteen patients were treated with open reduction and internal fixation for radial head fractures. Open reduction and internal fixation was performed to avoid radial head excision and the possible development of distal radioulnar joint dysfunction. Follow-up observation, which averaged 11.7 months, revealed that no patient developed wrist pain. Range of motion of the elbow and forearm was found to be complete in 14 patients and minimally restricted in four. Fourteen patients were pain free with full activity, and four had mild to moderate pain after heavy labor. One patient subsequently required radial head excision. Based on these findings and the authors continued disappointment with treatment of distal radioulnar joint dysfunction caused by proximal radial migration after radial head excision, the authors recommend early open reduction and internal fixation of all displaced or angulated radial head fractures.     

青年桡骨远端陈旧性骨折继发下尺桡关节重度脱位的手术治疗

目的 探讨青年桡骨远端陈旧性骨折继发下尺桡关节重度脱位的手术治疗方法.方法 采用短缩尺骨、重建下尺桡关节法,对7例桡骨陈旧性骨折、短缩,下尺桡关节重度脱位患者进行治疗.术后对患者腕关节外形、功能进行随访.结果 所有患者外形恢复良好,功能评价优6例,良1例.结论 短缩尺骨、重建下尺桡关节法是治疗桡骨陈旧性骨折、短缩,下尺桡重度脱位的有效方法.     

Graft reconstruction of the interosseous membrane in conjunction with metallic radial head replacement: a cadaveric study

PURPOSE: Longitudinal radioulnar dissociation (Essex-Lopresti injury) occurs when traumatic axial loading through the wrist disrupts the interosseous membrane (IOM) of the forearm and fractures the radial head. Proximal migration of the radius results in an ulnar-positive wrist, which can lead to painful ulnar-sided wrist degeneration and distal radioulnar joint instability. The purpose of this study was to measure the ability of an IOM reconstruction used in combination with a metal prosthetic radial head implant to reduce distal ulnar forces in a cadaveric model. The effects of varying the initial graft pretension on distal ulnar force were also studied. METHODS: Twelve fresh frozen and thawed cadaveric forearms had a miniature load cell installed to record force in the distal ulna as the wrist was loaded axially to 134 N of compression force in neutral rotation. Intact forearms were tested first with the elbow in valgus and varus alignments. Loading tests were repeated after (1) insertion of a metal radial head implant that restored radius anatomic length, (2) excision of the IOM (with a radial head implant), and (3) reconstruction of the IOM using a palmaris longus tendon autograft (with a radial head implant). The implant then was removed and loading tests were repeated using 3 levels of initial graft pretension. RESULTS: Mean distal ulnar forces with an intact forearm were 23% of applied wrist force in the varus alignment and 12% in the valgus alignment. Mean force levels after insertion of the implant were 18% (varus) and 13% (valgus); these were not significantly different from corresponding values for the intact forearm. Mean force levels after section of the IOM were 30% (varus) and 14% (valgus); these were not significantly different from corresponding values for the intact forearm (varus and valgus) but the mean for varus was significantly greater than the corresponding value with an implant. After IOM reconstruction with a palmaris longus tendon tensioned to 22 N mean distal ulnar forces were 8% (varus) and 7% (valgus); these means were significantly less than the corresponding values for all prior test conditions. With the radial head removed increasing the level of graft pretension reduced significantly mean distal ulnar force. CONCLUSIONS: With the IOM resected insertion of a metal radial head implant alone did not reduce distal ulnar forces to intact forearm levels. When an IOM reconstruction was performed in combination with the implant mean distal ulnar force was reduced significantly to a level below that for the intact forearm. Applying pretension to the graft displaced the radius distally thereby making the wrist more ulnar negative and reducing distal ulnar force. Our results suggest that an IOM reconstruction used in combination with a metal radial head implant theoretically could help reduce distal ulnar impaction in an Essex-Lopresti injury.     

Effects of radial head excision and distal radial shortening on load-sharing in cadaver forearms

BACKGROUND: The present study was performed to measure changes in radioulnar load-sharing in the cadaveric forearm following two orthopaedic surgical procedures that often have varying results: radial head excision and distal radial shortening. A better understanding of the biomechanical consequences of those procedures could aid surgeons in obtaining a more satisfactory clinical outcome. METHODS: Miniature load-cells were inserted into the proximal part of the radius and the distal part of the ulna in twenty fresh-frozen cadaveric forearms. Load-cell forces, radial head displacement relative to the capitellum, and local tension within the central band of the interosseous membrane were measured simultaneously as the wrist was loaded to 133.5 N in neutral pronation-supination and neutral radioulnar deviation. Testing was repeated after incremental distal radial shortening and after removal of the radial head. RESULTS: With the elbow flexed to 90 degrees and in valgus alignment (the radial head in contact with the capitellum), the mean force in the distal part of the ulna was 7.1% of the applied wrist force and the mean force in the interosseous membrane was 4.0%. With the elbow in varus alignment (a mean initial gap of 1.97 mm between the radial head and the capitellum), the respective mean values were 27.9% and 51.2%. After excision of the radial head, the mean force in the distal part of the ulna increased to 42.4% of the applied wrist force and the mean force in the interosseous membrane increased to 58.8%, in both varus and valgus elbow alignment. The mean distal ulnar force increased with progressive distal radial shortening in both varus and valgus elbow alignment; after 6 mm of radial shortening, the distal ulnar force averaged 92.4% (in varus alignment) and 60.9% (in valgus alignment). Equal distal load-sharing between the radius and ulna occurred after approximately 5 mm of radial shortening with the elbow in valgus alignment and after approximately 2 mm of radial shortening with the elbow in varus alignment. In valgus alignment, the force in the interosseous membrane was negligible after all degrees of radial shortening; in varus alignment, the mean force in the interosseous membrane decreased from 51.2% (0 mm of distal radial shortening) to 0% (6 mm of distal radial shortening) because of progressive slackening of the interosseous membrane. CONCLUSIONS: Radial head excision shifted the applied wrist force that normally would be transmitted to the elbow, through radial head-capitellar contact, to the interosseous membrane. The resulting proximal radial displacement created an ulnar-positive wrist and increased distal ulnar loading. Radial shortening and ulnar lengthening procedures have been designed to shift the applied wrist force from the distal part of the radius to the distal part of the ulna; it is commonly assumed that these procedures have equivalent biomechanical effects. We found that radial shortening resulted in slackening of the interosseous membrane, thereby negating its ability to transmit load through the forearm. Slackening of the interosseous membrane would not be expected with distal ulnar lengthening procedures. CLINICAL RELEVANCE: When the radial head has been fractured or excised, the mechanical status of the interosseous membrane is critical to the load-sharing process. If the interosseous membrane remains intact, distal ulnar loads will be limited to less than half of the applied wrist force; if the interosseous membrane has been damaged, nearly the entire applied wrist force will be shifted to the ulna. The amount of radial shortening or ulnar lengthening performed at the time of surgery during joint-leveling procedures has been largely empirical. We found that distal ulnar load increased by approximately 10% for each millimeter of radial shortening.     

Effect of radial shortening on muscle length and moment arms of the wrist flexors and extensors

The purpose of this study was to determine the effect of distal radial shortening on muscle length and moment arm of the wrist flexors and extensors. In eight cadaveric upper extremities, distal radius fractures were simulated by an ostectomy. The distal radius was progressively shortened by 2.5, 5.0, 7.5, and 10 mm. Changes in the resting length of the flexor carpi radialis and ulnaris, extensor carpi radialis longus and brevis, and extensor carpi ulnaris muscles were measured with rotary potentiometers at neutral position, flexion, extension, and radial and ulnar deviation of the wrists. The wrists were passively moved through flexion-extension and radioulnar deviation, and tendon excursions and wrist joint angulation were recorded simultaneously. Tendon moment arms were derived from tendon excursions and joint motion. The results showed that either muscle, length or moment arm of the principal wrist flexors and extensors was significantly affected by the radial shortening. Muscle length decreased significantly after radial shortening in all the wrist flexors and extensors except for the extensor carpi ulnaris. The moment arm of the extensor carpi ulnaris tendon decreased significantly during either wrist flexion-extension or radioulnar deviation. The extensor carpi radialis brevis and flexor carpi ulnaris tendons also showed a significant decrease in their moment arms during radioulnar deviation of the wrist. Radial shortening of only 2.5 mm caused statistically significant changes in muscle length and moment arm of the wrist flexors and extensors. Increasing the extent of radial shortening exaggerated the biomechanical changes in the wrist motors. These results validate the importance of normal radial length for wrist kinetics and, from a biomechanical perspective, support complete correction of radial shortening after distal radius fractures.     

Longitudinal radioulnar dissociation

Proximal translation of the radius is a complication of radial head fractures that occurs in association with disruption of the longitudinal soft-tissue stabilizers of the forearm. The sequelae of this process include debilitating wrist and elbow pain secondary to ulnocarpal and radiocapitellar abutment as well as loss of grip strength. When radioulnar dissociation is recognized early, treatment involves prevention of proximal radial migration by preservation of the radial head and stabilization of the distal radioulnar joint. When primary bony repair of the radial head is not feasible, prosthetic replacement of the radial head is necessary to prevent proximal radial migration. Management is complex in chronic cases in which longitudinal radioulnar dissociation is diagnosed after radial migration has occurred. Treatment goals include normalization of the radioulnar relationship and prevention of further migration. Although several reconstructive treatment options are available, no clear solutions exist, and long-term prognosis is guarded. Therefore, early recognition of longitudinal forearm instability is critically important.     

Reconstruction of the interosseous ligament unloads metallic radial head arthroplasty and the distal ulna in cadavers

PURPOSE: Longitudinal radioulnar dissociation may result when a compressive load to the hand results in excessive proximal migration of the radius with interosseous ligament (IOL) disruption and radial head fracture. Interosseous ligament reconstruction has been proposed to restore more normal forearm mechanics. The objective of this study was to evaluate the effect of IOL reconstruction on compressive load transfer through the forearm after excision and metallic replacement of the radial head in cadavers. METHODS: In 8 cadaveric forearms, 138 N of compressive load was applied to the hand in neutral forearm rotation and neutral elbow varus-valgus alignment. We measured proximal radial migration and 3-dimensional force vectors acting on the distal radius, distal ulna, IOL, proximal radius, and proximal ulna. The experiment was repeated in order for 5 conditions: (1) with the IOL intact, (2) with the IOL reconstructed with a double-bundle flexor carpi radialis construct, (3) with the radial head excised, (4) after metallic radial head arthroplasty, and (5) after cutting the IOL reconstruction. Analysis of variance was used for statistical comparisons. RESULTS: With the IOL intact the resultant load in the distal radius was 94% +/- 3% of hand load, with 75% +/- 2% transmitted to the proximal radius. Double-bundle flexor carpi radialis reconstruction effectively restored this relationship. After radial head excision the resultant distal radius load decreased whereas great increases were seen in the resultant distal ulna load, the resultant load in the IOL reconstruction, the resultant load in the proximal ulna, and proximal radial migration. Force continued to transfer through the proximal radius transversely, with a 400% increase in transverse force, a consequence of abutment of the radial stump caused by proximal radioulnar convergence (there was no contact at the capitellum). After radial head arthroplasty loads transferred across the wrist remained closer to intact but the resultant load on the distal ulna and proximal radius remained increased. With cutting of the IOL reconstruction transverse forces in the forearm became negligible, the resultant distal ulna load increased by 50%, and the resultant radial head load increased by 25%. Proximal migration of the radius was small and was increased by 4.6 mm with radial head excision and by 1 mm after radial head replacement compared with the IOL-reconstructed, radial head-intact state. CONCLUSIONS: Interosseous ligament reconstruction may help improve treatment of longitudinal radioulnar dissociation but remains an experimental procedure.     

The Essex-Lopresti lesion: a variant with a bony distal radioulnar joint injury

The Essex-Lopresti lesion is an unusual injury, consisting of a radial head or neck fracture, distal radioulnar joint (DRUJ) injury and interosseous membrane rupture. To date, all reported Essex-Lopresti lesions have consisted of soft tissue injuries at the DRUJ. We present a case of an Essex-Lopresti lesion with a bony variant, in which the DRUJ injury consisted of an ulnar head fracture associated with radial head fracture and acute proximal migration of the radius. The management involved plating of the ulnar head fracture and titanium replacement of the radial head.     

Ulnar wrist pain after Colles' fracture: 109 fractures followed for 4 years

109 patients with unilateral Colles' fracture, treated with closed reduction and cast immobilization, were re-examined after 4 (1-9) years. At follow-up, 40 patients had persistent ulnar wrist pain. The most important factor for predicting ulnar pain was final dorsal angulation of the radius. Initial and final radial shortening, fracture of the distal radioulnar joint, ulnar styloid fracture, or instability of the distal ulna were not correlated to ulnar wrist pain. We suggest that ulnar wrist pain following Colles' fracture is caused by incongruity of the distal radioulnar joint.     

Mechanisms of load transfer in the cadaver forearm: role of the interosseous membrane

Forces transmitted through the distal ulna and proximal radius, relative motion between the radial head and capitellum, and measurements of tissue strain and local fiber tension within the central band of the interosseous membrane were recorded as cadaveric forearms were loaded axially through the wrist. With the elbow in valgus alignment (the radial head in direct contact with the capitellum), an average of 93% of force applied to the wrist was transferred directly through the radius to the elbow with no appreciable load transfer through the interosseous membrane. With varus alignment (initial gap between the radial head and capitellum) load applied to the wrist displaced the radius proximally an average of 1.1 mm until radial head contact occurred at a mean applied wrist force of 89.0 N. Proximal displacement of the radius generated strain in the central band of the interosseous membrane and created a more ulnar positive wrist, which in turn increased distal ulnar loading; distal ulnar force averaged 19% and interosseous membrane averaged 54% of applied wrist force. Distal ulnar loading was unaffected by 25 degrees wrist flexion-extension or by 20 degrees of radioulnar deviation. With 40 degrees ulnar deviation, mean distal ulnar forces were 18% and 48% of applied wrist force for valgus and varus elbow alignments, respectively. Mean load-sharing percentages at the wrist and elbow were not significantly different between 222. 5 N and 133.5 N of applied force for any wrist position and were unaffected by the angle of elbow flexion.     

Load-sharing at the wrist following radial head replacement with a metal implant. A cadaveric study

BACKGROUND: Surgical excision of the radial head is frequently required after a comminuted fracture of the radial head. The outcome of this procedure is often unpredictable, with some patients experiencing ulna-sided pain in the wrist secondary to proximal migration of the radius. Insertion of a radial head prosthesis could prevent proximal radial migration and restore normal load-sharing at the wrist. The thickness of the radial head implant is an important variable in restoring anatomical radial length; however, the effects of varying the length of implants that were used to reconstruct the radius on load-sharing at the wrist have not been studied biomechanically, to our knowledge. METHODS: A miniature load cell was attached to fifteen fresh-frozen cadaveric forearms to record force in the distal part of the ulna as the wrist was axially loaded to 134 N of compression force. Proximal displacement of the radius relative to the capitellum was also recorded. Loading tests on intact forearms were performed with the elbow in valgus and varus alignment and with three positions of wrist rotation (neutral, 45 degrees of pronation, and 45 degrees of supination). Loading tests were then repeated, with the same positions of varus and valgus elbow alignment and wrist rotation as had been used in the tests of the intact forearm, after radial head excision and subsequent insertion of metal radial head implants that restored anatomical length, implants that produced a radial length that was longer than the anatomical length, and implants that produced a radial length that was shorter than the anatomical length. Testing of these different implant thicknesses was repeated after sectioning of the interosseous membrane. RESULTS: The mean distal ulnar forces and mean proximal radial displacements following insertion of an implant that restored anatomical length were not significantly different from the corresponding values for the intact forearm. At neutral wrist rotation, replacing that implant with an implant that increased the radial length by 4 mm (after sectioning of the interosseous membrane) decreased the mean distal ulnar force from 13.4% to 3.3% of the applied wrist force with the elbow in valgus alignment and from 29.1% to 8.6% with the elbow in varus alignment. Replacing the implant that restored anatomical length with one that decreased the length by 4 mm (after sectioning of the interosseous membrane) significantly increased the mean distal ulnar force from 13.4% of the applied wrist load to 33.3% with the elbow in valgus alignment and from 29.1% to 51.6% with it in varus alignment. The mean distal ulnar forces were not significantly affected by the position of wrist rotation when the elbow was in valgus alignment. However, when the elbow was in varus alignment, the mean distal ulnar forces associated with all reconstructed radial lengths were significantly higher when the wrist was placed in 45 degrees of supination. CONCLUSIONS: In this cadaveric model, insertion of a metal implant maintained distal ulnar forces at normal levels, at all three positions of wrist rotation, when the radius had been restored to its original anatomical length. Distal ulnar forces and proximal radial displacements were significantly affected by the reconstructed length of the radius. CLINICAL RELEVANCE: Radial head implants are utilized to prevent proximal migration of the radius as the wrist is loaded; this is especially important when the interosseous membrane has been ruptured and thus cannot help to limit radial displacement. At the time of surgery, comminution and displacement of a radial head fracture may make estimation of the original radial length difficult. Our results demonstrate that, in terms of distal ulnar loading, it is preferable to insert an implant that is too thick rather than too thin.     

Operations for forearm deformity caused by multiple osteochondromas

We reviewed 36 cases of forearm deformity caused by multiple osteochondromas in 30 patients and classified them into three types: Type I showed a combination of ulnar shortening and bowing of the radius secondary to osteochondromas of the distal ulna (22 forearms). Type II showed dislocation of the radial head, either with osteochondromas of the proximal radius (Type IIa, two forearms) or secondary to more distal involvement (Type IIb, five forearms). Type III had relative radial shortening due to osteochrondromas at the distal radius (seven forearms). Operations were performed on 16 forearms in 13 patients, with 92% of satisfactory results. For Type I deformity, excision of osteochondromas, immediate ulnar lengthening and corrective osteotomy of the radius are recommended. For Type IIa, excision of the radial head is necessary, and for Type IIb, we advise gradual lengthening of the ulna using an external fixator. Excision of osteochondromas alone gave good results in Type III deformity. Our classification gives a reliable indication of the prognosis and is a guide to the choice of surgical treatment.     

Distal radioulnar joint injuries

Distal radioulnar joint is a trochoid joint relatively new in evolution. Along with proximal radioulnar joint, forearm bones and interosseous membrane, it allows pronosupination and load transmission across the wrist. Injuries around distal radioulnar joint are not uncommon, and are usually associated with distal radius fractures,fractures of the ulnar styloid and with the eponymous Galeazzi or Essex_Lopresti fractures. The injury can be purely involving the soft tissue especially the triangular fibrocartilage or the radioulnar ligaments. The patients usually present with ulnar sided wrist pain, features of instability, or restriction of rotation. Difficulty in carrying loads in the hand is a major constraint for these patients. Thorough clinical examination to localize point of tenderness and appropriate provocative tests help in diagnosis. Radiology and MRI are extremely useful, while arthroscopy is the gold standard for evaluation. The treatment protocols are continuously evolving and range from conservative, arthroscopic to open surgical methods. Isolated dislocation are uncommon. Basal fractures of the ulnar styloid tend to make the joint unstable and may require operative intervention. Chronic instability requires reconstruction of the stabilizing ligaments to avoid onset of arthritis. Prosthetic replacement in arthritis is gaining acceptance in the management of arthritis.     

Mar shortening osteotomy in posttraumatic ulnar impaction syndrome

Twenty-eight patients (average age 45 years) with posttraumatic ulnar impaction syndrome underwent ulnar shortening osteotomy of 3–15 mm. Contributing factors were malunited fractures of the distal radius in 20, diaphyseal fractures of the ulna and radius in 6, resection of the radial head and a traumatic tear of the triangular fibrocartilage in 1 patient each. Evaluation at an average follow-up of 20 months showed a high rate of satisfied patients (89%), but according to Chun's modification of the Gartland-Werley score there were 1 excellent (3.5%), 11 good (39.5%), 11 fair (39.5%) and 5 poor (17.5%) results. Degenerative changes of the distal radioulnar joint were associated with fair and poor results, and ulnar shortening osteotomy is only recommended in ulnocarpal impaction with an intact distal radioulnar joint. Osteotomy fixation with 3.5 mm dynamic compression plates enabled immediate postoperative mobilisation and resulted in a low complication rate. There was no advantage for the technically more demanding oblique as compared with a transverse osteotomy.     

Ulnar bursa distention following volar subluxation of the distal radioulnar joint after distal radial fracture: a rare cause of carpal tunnel syndrome

This report describes an eighty-four-year-old woman with persistent carpal tunnel syndrome attributable to an ulnar bursa distention associated with the subluxation of the distal radioulnar joint after distal radial fracture. During surgery, when the forearm was placed in supination, the ulna head with a sharp osteophyte was found to be displaced into the carpal tunnel through a defect of the ruptured capsule of the wrist joint. This volar subluxation of the ulnar head had caused distention of the ulnar bursa, causing compression of the median nerve, which resulted in carpal tunnel syndrome. In addition to reduce displaced fractured segment to obtain anatomic articular surface, original radial length and tilt, the anatomic restoration of the distal radioulnar joint is essential to maintain better long-term function after fracture of the distal radius.     

The value of plain X-rays in predicting TFCC injury after distal radial fractures

In this prospective study, the plain X-rays and MRI scans of 60 patients with intraarticular distal radius fractures were examined in random order. MRI evaluation revealed that 27 of the 60 patients (45%) had triangular fibrocartilage lesions. No correlation was found between triangular fibrocartilage injury and the Melone classification system, the presence of an ulnar styloid fracture, comminution of the articular surface of the distal radius, >20 degrees dorsal angulation of the distal radius or subluxation/dislocation of the distal radioulnar joint on the plain X-rays. When Frykman Type VI and VIII fractures were compared with all the other Frykman subtypes, a significant difference in the incidence of triangular fibrocartilage complex tears was observed. We conclude that triangular fibrocartilage injury should be considered with all distal radial fractures, especially the Frykman Types VI and VIII.     

桡骨远端骨折对下尺桡关节稳定性的影响

目的:分析桡骨远端骨折后腕部功能与下尺桡关节稳定性之间的关系,探讨桡骨远端骨折影响下尺桡关节稳定性的原因。方法:85例桡骨远端骨折患者,男27例,女58例;年龄17~74岁,平均42.3岁。采用手法复位石膏外固定治疗,伤后6~9个月(平均6.7个月)摄腕关节正侧位X线CR片,检查下尺桡关节稳定性,采用Sarmiento改良的Gartland-Werley评分系统(GW评分)对腕部进行功能评估。结果:85例获得6~9个月随访,平均6.7个月。19例有下尺桡关节不稳定。下尺桡关节不稳与放射学检查下尺桡关节情况之间无明显的联系。下尺桡关节不稳的患者GW评分平均为12.37±5.899,稳定的患者GW评分平均为6.85±4.222,差异有统计学意义。尺骨茎突是否骨折其GW评分差异无统计学意义。是否有尺骨茎突骨折其下尺桡关节不稳发生率比较差异无统计学意义。结论:明显成角或短缩畸形的桡骨远端骨折损伤三角纤维软骨复合体可能是造成下尺桡关节不稳、影响腕部功能的主要原因。伴随桡骨远端骨折的尺骨茎突骨折对下尺桡关节稳定性无明显影响。     

Gelenkflächenverhalten der Articulatio radioulnaris distalis bei fehlgestelltem distalem Radius

Pathological changes of wrist bones and ligaments after radial fracture loco typico induce permanent functional restriction and pain. In this paper the effects of malunion on the distal radioulnar joint are investigated and osteotomic therapy of Kinenböck's disease gets a new evaluation. By simulating radial malunions on anatomic forearm specimen the effects of these malunions on the contact area during supination, neutral position and pronation are measured. Isolated posttraumatic radial shortening as well as epiphyseal inclination and torsion cause a reduction of radioulnar contact. During supination and pronatijon the loss of radioulnar contact increases. Most significant reduction of contact takes place at a lower graduation of radial malunion. Pronatory torsion of distal radius compensates for a radioulnar contact reduction from combining dorsal inclination with radial shortening. One conclusion of this paper is an exact restitution of anatomical relations between ulnar head and radial notch after fracture of the distal radius.     

A biomechanical study of distal radial fractures

In an attempt to explain disability in dorsally angulated malunited distal radius fractures, an experiment was designed to evaluate load patterns about the wrist with varying degrees of dorsal angulation of the distal radius. Osteotomies were made in the distal radius of fresh cadaver arms after a modified external fixator was applied to the radius and load cells applied to the proximal radius and ulna. Pressure-sensitive film was inserted into the radioulnar carpal joint. After a predetermined load was applied to the wrist it was found that the load through the ulna increased from 21% to 67% of the total load as the angulation of the distal radial fragment increased from 10 degrees of palmar tilt to 45 degrees of dorsal tilt. The pressure distribution on the ulnar and radial articular surfaces changed in position and became more concentrated as dorsal angulation increased.     

Allograft replacement with distal radioulnar joint fusion and ulnar osteotomy for treatment of giant cell tumors of the distal radius

Three patients with advanced giant cell tumors of the distal radius received a frozen allograft replacement of the distal radius, accompanied by a distal radioulnar arthrodesis with ulnar osteotomy proximal to the wrist. Follow-up ranged from 2 to 4 years. During this time this combined procedure provided the following advantages: complete tumor resection, no donor site morbidity, retention of pronation-supination, and avoidance of pain or subluxation at the distal radial ulnar joint.