The effects of distal radius fracture malalignment on forearm rotation: a cadaveric study

Use of homologous bone graft in the treatment of aseptic forearm nonunion

The dyaphyseal nonunion of forearm bones is a complication that changes the normal interaction between radius and ulna, which may lead to forearm malfunction. We reviewed 14 patients treated by surgical technique included a homologous bone graft in combination with a plate. The mean age was 31 years (range, 18-45 years) at the time of surgery. Minimum follow-up was 2 years (mean, 5 years; range, 2-13 years). There were no intraoperative or postoperative complications. At last follow-up, all forearm bones had remodelled. The mean visual analogue pain scale was 1 (range, 0-4). There was a high success rate regarding forearm alignment and functional results; all patients recovered daily and working activities quickly. This surgical technique in treatment of aseptic forearm nonunion by combining homologous bone graft with a plate led to bone healing, improved forearm function, and a durable outcome with long-term follow-up.

Repositioning osteotomy for intra-articular malunion of distal radius with radiocarpal and/or distal radioulnar joint subluxation

BACKGROUND

Intra-articular malunion of the distal radius may be complicated with radiocarpal and radioulnar joint subluxation, which may result in joint stiffness and loss of function. Conventional corrective osteotomy emphasizes on the restoration of the articular step-off. However, little information is available concerning the restoration of a concentric functioning joint through osteotomy.

METHODS

From 2002 to 2007, 12 patients with chronic intra-articular distal radius fractures were evaluated at an average follow-up of 33.6 months after repositioning osteotomy. The average time from initial injury to reconstructive operation was 11.3 months. The indication for osteotomy included dorsal or volar subluxation of the radiocarpal joint, distal radioulnar joint, or both in addition to articular incongruity. A preoperative computed tomography scan or rapid prototyping (RP) models were performed as part of the surgical planning. Operation was preceded by volar, dorsal, or both approaches. Repositioning osteotomy and internal fixation were also performed. Radiographic analysis and the Disability of Arm, Shoulder and Hand score were used for the outcome assessment.

RESULTS

All osteotomy sites healed and all events of radiocarpal and radioulnar subluxation were corrected. The average correction was 13.8 degrees (palmar tilt of the radius) and 1.9 mm in ulnar variance. The mean Disability of Arm, Shoulder and Hand score improved from 64 to 18.

DISCUSSION

Conventional corrective osteotomy via an extra-articular approach was favorably performed to correct an extra-articular malalignment or nascent intra-articular malunion. Problems of abnormal architecture after an intra-articular fracture of the radius are complicated with subluxation of carpus or distal radioulnar joint, which require repositioning via precise articular approach. Both reconstructed computed tomography images and rapid prototyping models are very useful tools in preoperative planning for intra-articular osteotomy. Simulated osteotomy and joint repositioning can be performed in solid models before commencement of actual operation.

CONCLUSION

Repositioning osteotomy consistently restores joint alignment and achieves functional improvement either in cases of nascent simple malunion or complex intra-articular malunion.

Correlation of malrotation deformity in distal radius fractures with radiographic analysis: cadaveric study

PURPOSE

The radiographic parameters commonly used for evaluating distal radius fractures are radial length, palmar tilt, radial inclination, and articular congruity. Rotation of the distal fragment is not routinely evaluated after distal radius fractures. The purpose of this study was to define the appearance of distal fragment malrotation on conventional radiographs and to correlate varying degrees of malrotation with the corresponding radiographic findings.

METHODS

Six distal radiuses from embalmed cadavers were cut and stabilized in 10 degrees, 20 degrees, and 30 degrees of pronated malrotation. Posteroanterior, lateral, and oblique (45 degrees pronated view) radiographs were taken and radiographic measurements were made of radial length, palmar tilt, radial inclination, and rotation.

RESULTS

With malrotation, the visible cortical width of the distal fragment mismatched the visible cortical width of the proximal fragment. This was most evident on the oblique view (p < .05) and measured 2.2 mm for 10 degrees of rotation (standard deviation [SD] 0.6), 3.4 mm for 20 degrees of rotation (SD 0.8), and 5.3 mm for 30 degrees of rotation (SD 2.2).

CONCLUSIONS

The radiographic parameter of rotation should be considered when evaluating distal radius fracture reduction. Malrotation is best seen on a 45 degrees oblique pronated radiographic view as a mismatch of the cortical width of the distal fragment compared with the cortical width of the proximal fragment. In the absence of radial shortening, a 5.3-mm mismatch is associated with 30 degrees of malrotation and is the upper limit of acceptability.

Management of post-traumatic malunion of fractures of the distal radius

Distal radius malunions are a common cause of patient morbidity. This review of the literature surrounding distal radius malunion covers the demographics, pathologic anatomy, and indications for surgery, surgical techniques, and salvage options. Particular emphasis is placed on subject areas that have not been reviewed as extensively in previous articles, including: intra-articular malunion, computer-assisted techniques, bone graft alternatives, and volar fixed-angle plate osteosynthesis.

Aseptic forearm nonunions treated by plate and opposite fibular autograft strut

Forearm nonunion frequently changes the relationship between the radius and ulna and may lead to impairment of forearm function. We propose a new surgical technique for aseptic forearm nonunions combining a fibular cortical autograft strut with a metal plate and a fibular intercalary autograft in cases with a segmental bone defect. We retrospectively reviewed 20 patients with a mean age of 31 years (range, 17-48 years) at the time of surgery. Minimum followup was 12 years (mean, 14 years; range, 12-21 years). There were no intraoperative or postoperative complications. At last followup, all forearm bones had remodeled. The mean visual analog pain scale was 1 (range, 0-3). Forearm function improved; there were no radiographic signs of ankle arthritis at followup. Surgical treatment of aseptic forearm nonunions by combining a massive fibular cortical autograft strut with a plate and associating a fibular intercalary autograft in case of a segmental bone defect led to bone healing, improved forearm function, and a durable outcome with long-term followup.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

The effect of multiplanar distal radius fractures on forearm rotation: in vitro biomechanical study

PURPOSE

Many patients develop distal radioulnar joint (DRUJ) pain and loss of forearm rotation after distal radial fractures. Residual distal radial deformity is one potential cause of DRUJ dysfunction; however, the parameters of distal radial fracture alignment that lead to an acceptable functional outcome are poorly defined in the literature.

METHODS

We used 8 fresh-frozen cadaveric specimens in this in vitro study to examine the effect of simulated distal radius fracture misalignment on forearm rotation. A distal radial osteotomy was performed just proximal to the DRUJ and a custom-made, 3-degrees-of-freedom modular implant designed to simulate distal radius fracture deformities was secured in place. This allowed for accurate simulation of dorsal angulation, dorsal translation, and radial shortening, both independently and in combination. We examined the effects of distal radius deformity in the setting of both an intact and sectioned triangular fibrocartilage complex.

RESULTS

Pronation was not significantly affected until dorsal angulation reached 30 degrees . Dorsal translation of up to 10 mm or radial shortening up to 5 mm had no effect on forearm rotation. Combined deformities had a greater effect on forearm motion than isolated malpositions. Dorsal angulation of > or =20 degrees combined with 10 mm of dorsal translation or 20 degrees of angulation with 2.5 mm of radial shortening resulted in a significant decrease in forearm pronation. There was no effect of distal radial deformities, either isolated or combined, on the magnitude of forearm rotation after sectioning the triangular fibrocartilage complex.

CONCLUSIONS

This study demonstrates that a broad range of distal radius fracture malpositions can be tolerated before a notable loss in forearm range of motion is evident. Combined deformities are more likely to result in a clinically important loss of forearm rotation, and this should be considered when choosing the optimal management of patients with displaced distal radial fractures. Disruption of the triangular fibrocartilage releases the tether on the DRUJ, allowing for preservation of forearm motion even in the setting of marked osseous deformities.

Assessment of distal radioulnar joint instability after distal radius fracture: comparison of computed tomography and clinical examination results

PURPOSE

To compare computed tomography (CT) and clinical stress test findings in terms of the assessment of distal radioulnar joint (DRUJ) instability after distal radius fracture.

METHODS

Thirty-four patients with a healed unilateral distal radius fracture were evaluated after a mean follow-up period of 18 months. Stress test and CT were performed to detect DRUJ instability. Three CT methods were used: the modified radioulnar line, the epicenter, and the radioulnar ratio methods. The results of CT assessments were compared with stress test findings using kappa statistics. Relationships between DRUJ instability and the radiographic parameters of volar tilt, radial inclination, and radial shortening were analyzed.

RESULTS

Twelve patients were considered to have DRUJ instability based on the stress test. DRUJ instability was diagnosed in 15, 8, and 11 patients by the modified radioulnar line, the epicenter, and the radioulnar ratio methods, respectively. Reliability analysis of stress test and CT results showed moderate or fair agreement (kappa value: .33 for the modified radioulnar line, .56 for the epicenter, .41 for the radioulnar ratio). DRUJ instability diagnosed by the stress test and by CT showed no statistical correlation with radiographic parameters, but instability determined by CT appeared to be related to dorsal tilt deformity.

CONCLUSIONS

After distal radius fracture, CT assessments of DRUJ instability were found to be influenced by residual deformities, such as dorsal tilt, but not well correlated with stress test findings. Although CT assessments are objective, CT scans primarily show alterations of DRUJ alignment and have several risks of bias in patients with a prior distal radius fracture.

Osteotomy of dorsally displaced malunited fractures of the distal radius: no loss of radiographic correction during healing with a minimally invasive fixation technique and an injectable bone substitute

BACKGROUND AND PURPOSE

Malunion after a distal radius fracture can be treated with an osteotomy of the distal radius. Often autologous iliac crest bone graft is used to fill the gap, but this is associated with donor site morbidity. Instead of bone graft, we have used a slow-resorbing bone substitute in combination with a minimally invasive fixation technique.

PATIENTS AND METHODS

25 consecutive patients with a dorsal malunion after a distal radius fracture underwent an osteotomy. A TriMed buttress pin and a radial pin plate were used for fixation, and Norian SRS as bone substitute. The patients were followed for a minimum of 1 year and range of motion, grip strength, DASH scores, and the radiographic correction were measured.

RESULTS

Forearm rotation improved from 137 degrees to 155 degrees , flexion/extension from 102 degrees to 120 degrees , and radioul-nar deviation from 32 degrees to 43 degrees . Grip strength increased from 62% of the contralateral hand to 82%. DASH scores decreased from 36 to 23. Radiographically, all osteotomies but 1 healed and the radiographic correction achieved was consistent over the first year.

INTERPRETATION

Osteotomy of the distal radius is effective in increasing motion and grip strength after a malunited distal radial fracture. Patient satisfaction is high and subjective results measured with DASH are good. Using a bone substitute, the operation can be performed as an outpatient procedure and donor-site pain avoided. No loss of the radiographic correction achieved was noted during osteotomy healing.

Effects of distal radius malunion on distal radioulnar joint mechanics--an in vivo study

Patients with a malunited distal radius often have painful and limited forearm rotation, and may progress to arthritis of the distal radioulnar joint (DRUJ). The purpose of this study was to determine if DRUJ congruency and mechanics were altered in patients with malunited distal radius fractures. In nine subjects with unilateral malunions, interbone distances and dorsal and palmar radioulnar ligament lengths were computed from tomographic images of both forearms in multiple forearm positions using markerless bone registration (MBR) techniques. The significance of the changes were assessed using a generalized linear model, which controlled for forearm rotation angle (-60 degrees to 60 degrees ). In the malunited forearm, compared to the contralateral uninjured arm, we found that ulnar joint space area significantly decreased by approximately 25%, the centroid of this area moved an average of 1.3 mm proximally, and the dorsal radioulnar ligament elongated. Despite our previous findings of insignificant changes in the pattern of radioulnar kinematics in patients with malunited fractures, we found significant changes in DRUJ joint area and ligament lengthening. These findings suggest that alterations in joint mechanics and soft tissues may play an important role in the dysfunction associated with these injuries.

Management of post-traumatic malunion of fractures of the distal radius

Distal radius malunions are a common cause of patient morbidity. This review of the literature surrounding distal radius malunion covers the demographics, pathologic anatomy, and indications for surgery, surgical techniques, and salvage options. Particular emphasis is placed on subject areas that have not been reviewed as extensively in previous articles, including: intra-articular malunion, computer-assisted techniques, bone graft alternatives, and volar fixed-angle plate osteosynthesis.

Immediate mobilisation following corrective osteotomy of distal radius malunions with cancellous graft and volar fixed angle plates

The purpose of the study was to examine the reliability with which a specific technique of corrective osteotomy of malunions of the distal radius combined with early mobilisation could both restore the normal anatomic parameters of the radius and achieve a functional range of motion with good strength. Corrective osteotomy of the distal radius was performed through a volar approach using a fixed angle volar plate and cancellous bone graft from the iliac crest in 19 patients of mean age 50 years with initial malunions with a mean dorsal tilt of 36 degrees and 7 mm of ulnar variance. An immediate mobilisation programme was started. All healed at a mean of less than 12 weeks (including two heavy smoking patients who required repeat cancellous bone grafting to achieve final union) to achieve a total arc of wrist motion around 120 degrees, forearm rotation of 158 degrees and grip strength which was 80% of contralateral. This treatment strategy was judged to be straightforward and effective.

Malunion of the distal radius

Fractures of the distal radius are common injuries. Acceptable results typically can be obtained with appropriate surgical or nonsurgical management. However, a small percentage of these fractures can progress to symptomatic malunion, which traditionally has been treated with osteotomy of the distal radius. Proper understanding of anatomy, biomechanics, indications, and contraindications can help guide patient selection for surgery. In formulating a treatment plan, the surgeon also must consider such technical variables as the type of osteotomy, the use of bone graft or bone-graft substitute, and the means of fixation to stabilize the osteotomy. Simultaneous implementation of an ulnar-side procedure, an intra-articular osteotomy, and soft-tissue releases also may be necessary. Some cases may be more appropriate for wrist fusion or other salvage procedures.

Volar fixed-angle plating of distal radius extension fractures: influence of plate position on secondary loss of reduction--a biomechanic study in a cadaveric model

PURPOSE

Treatment of extension fractures of the distal radius with volar fixed-angle plates has become increasingly popular in the past 2 years. It has been observed clinically that placement of the distal screws as close as possible to the subchondral zone is crucial to maintain radial length after surgery. The purposes of this study were (1) to evaluate radial shortening after plating with regard to plate position and (2) to evaluate whether plate position has an influence on the strength and rigidity of the plate-screw construct.

METHODS

An extra-articular fracture (AO classification, A3) was created in 7 pairs of fresh-frozen human cadaver radiuses. The radiuses then were plated with a volar distal radius locking compression plate. Seven plates were applied subchondrally; 7 plates were applied 4.5 mm to 7.5 mm proximal to the subchondral zone. The specimens were loaded with 800-N loads for 2,000 cycles to evaluate radial shortening in the 2 groups. Each specimen then was loaded to failure.

RESULTS

Radial shortening was significantly greater when the distal screws were placed proximal to the subchondral zone. The amount of shortening after cyclic loading correlated significantly with the distance the distal screws were placed from the subchondral zone. Rigidity of the plate systems was significantly higher in radiuses in which the distal screws were placed close to the subchondral zone.

CONCLUSIONS

To maintain radial length after volar fixed-angle plating, placement of the distal screws as subchondral as possible is essential. The subchondral plate-screw-bone constructs showed significantly greater rigidity, indicating higher resistance to postoperative loads and displacement forces.

Cal vicieux du radius en flexion

AIMS

In this paper we will differentiate the clinical management of distal radial fractures with malunion in extension from those with malunion in flexion. Malunions in flexion are rare and radial shortening does not contribute significantly to the deformity. There is always a decrease in the range of motion, especially prono-supination. Besides the usual causes of these malunions, a new iatrogenic cause is becoming prevalent: malunion in flexion occurs when a fracture in extension is treated by posterior intrafocal pinning but the surgery is performed poorly or performed when it is contra-indicated because of volar comminution.

PATIENT AND METHODS

We report a retrospective study of 20 cases of distal radius malunion in flexion. The series includes relatively young patients with a mean age of 39.3 of age (24-66). Three types of surgery are compared: 1) an isolated radius extension osteotomy (group 1); 2) an isolated procedure on the ulna (group 2); 3) combined procedures on radius and ulna (Group 3).

RESULTS

Results of the three techniques on prono-supination are almost the same, resulting in an almost normal range of motion. Pain decreased from 2.1 (pain for significant strains) to 0.7 (no or climatic pain) in a five-scale classification from 0 to 4. Strength increased by 23% to reach 83.3% of the opposite side. Some differences with malunions in extension should be noted: 1) volar carpal subluxation relative to the radius is present in less than 1/3 of the cases (6/20); 2) adaptive carpus is very rare and independent of the volar displacement (2/20), 3) palmar flexion exists without significant shortening (bone graft rarely necessary); 4) Pronation of the distal fragment results in distal radioulnar joint incongruity.

INDICATIONS

The best treatment for young patients is combined radial and ulnar osteotomy. Although a more radical procedure, it is worthwhile for the younger patient in order to recover normal anatomy. Isolated radial osteotomy may be sufficient if pronosupination and radioulnar joint congruity are regained. However, isolated procedures on the distal ulna are only indicated in the elderly, or in patients with little discomfort.

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.

A meta-analysis of outcomes of external fixation versus plate osteosynthesis for unstable distal radius fractures

PURPOSE

External fixation and open reduction and internal fixation have been the traditional techniques for surgical fixation of unstable distal radius fractures. The existing literature has not identified which is superior, primarily because of the lack of comparative trials. We performed a comprehensive systematic review and meta-analysis of the current literature on external fixation and internal fixation of distal radius fractures to determine the dominant strategy based on available scientific evidence.

METHODS

We searched MEDLINE and EMBASE for English-language articles published between 1980 and 2004 that satisfied predetermined inclusion and exclusion criteria. The outcomes of internal and external fixation were compared using continuous measures of grip strength, wrist range of motion, and radiographic alignment and categoric measures of pain, physician-rated outcome scales, and complication rates. Outcomes were pooled by random-effects meta-analysis and meta-regression analysis was used to control for patient age, presence of intra-articular fracture, duration of follow-up period, and date of publication. Sensitivity analyses were used to test the stability of the meta-analysis results under different assumptions.

RESULTS

Forty-six articles were included in the review with 28 (917 patients) external fixation studies and 18 (603 patients) internal fixation studies. Meta-analysis did not detect clinically or statistically significant differences in pooled grip strength, wrist range of motion, radiographic alignment, pain, and physician-rated outcomes between the 2 treatment arms. There were higher rates of infection, hardware failure, and neuritis with external fixation and higher rates of tendon complications and early hardware removal with internal fixation. Considerable heterogeneity was present in all studies and adversely affected the precision of the meta-analysis.

CONCLUSIONS

The current literature offers no evidence to support the use of internal fixation over external fixation for unstable distal radius fractures. Comparative trials using appropriately sensitive and validated outcome measurements are needed to guide treatment decisions.

Rehabilitation of distal radius fractures: a biomechanical guide

Fracture healing and surgical decision making are not always predictable. The suggested protocols are intended to be flexible rather than rigid to be responsive to patient progress and the fracture site stability. A methodologic approach to the rehabilitation following a distal radius fracture, based on a knowledge of the biology of fracture healing and biomechanics of fixation, may preempt some of the pitfalls associated with distal radius fracture healing.

Extra-articular distal radial fracture malunion

With the increase in surgical options for the treatment of distal radius fractures, the authors anticipate that distal radial fracture malunions will be a less frequently seen problem. Nevertheless, they will still occur. Although patient selection has been weighted toward the younger patient, we believe that surgery should be based on patient activity level, functional needs, and disability related to the malunion. With advances in biotechnology and improved anesthetics, surgical intervention even in the older and osteopenic population is now more promising. Surgical intervention still requires appropriate patient selection, careful preoperative planning, and meticulous surgical technique. The appropriate surgical procedure should be tailored to the patient's symptoms, age, needs, and radiographic findings.

Predicting the outcome of distal radius fractures

There are myriad factors that affect patient satisfaction following a distal radius fracture, including anatomic alignment, age, motion, pain,and hand dominance to name a few. The seeming contradictions in the literature serve to illustrate that individual outcomes are not entirely predict-able because of the different functional demands,expectations, and pain tolerance for each patient. Elderly populations may tolerate greater degrees of residual deformity because of a more sedentary lifestyle. Unrecognized intracarpal pathology may account for poor results despite acceptable radiographic alignment. Possessing a knowledge of the predictive factors that affect adversely the functional outcome, however, does allow the surgeon to manage complications proactively to maximize the potential for an acceptable end result.

Combined fractures of the scaphoid and distal radius: a revised treatment rationale using percutaneous and arthroscopic techniques

Revision of the treatment rationale for combined fractures of the scaphoid and distal radius is based on evolution of treatment goals. The trend toward early recovery of hand function requires rigid fixation of both fractures before the start ofa hand therapy program. It is clear that prolonged immobilization of the scaphoid fracture jeopardizes early motion protocols for the distal radius. The fixation of unstable distal radius fractures with volar locking plates appears to offer the most stable construct to permit early motion. Evaluation, reduction, and fixation should be accomplished without disruption of the uninjured ligaments required for stable motion or the soft tissue envelope required for healing. Minimally invasive or percutaneous techniques are the meth-ods required. The tools needed are a clear understanding of anatomy, minifluoroscopic imaging units, and small-joint arthroscopy instruments. Many investigators advocate these techniques for scaphoid and distal radius fractures. It is only natural that these techniques should be used for these combined injuries. The key to success is a three-step process: (1)percutaneous reduction of the scaphoid fracture and provisional stabilization with a guide wire placed along its central axis, (2) percutaneous/arthroscopic reduction and rigid fixation of the distal radius fracture to permit early motion, and(3) fixation of the scaphoid fracture. This final step is accomplished by dorsal percutaneous implantation of a cannulated headless compression screw along the central scaphoid axis. Dorsal percutaneous fixation of scaphoid fractures with headless compression screws and rigid fixation of unstable distal radius fractures with a volar lock-ing plate system offer the most secure fixation. This small series suggests that the goals of early recovery of hand function can be accomplished using percutaneous/miniopen techniques for fracture reduction with rigid fixation and minimal risks.

Distale Radiusfraktur

Distal fracture of the radius is an injury to a complex joint that is comprised functionally of four partial joints and makes it possible for the hand to move in all directions. The injuries to bone and cartilage and to the stabilizing ligamentous structures and the surrounding soft tissue vary as functions of the impact responsible, the mechanism of injury, and any previous illnesses. The objectives of treatment are restoration of pain-free, unrestricted and lasting function of the wrist and lower arm and avoidance of the typical complications. Stable fractures are treated by conservative means, while unstable fractures with fragmentation are realigned in a closed procedure and then stabilized by internal or external fixation. In the case of fractures in bones affected by osteoporosis it is usually not necessary to make good a metaphyseal defect when specially adapted fixed-angle plates are used. Complex intraarticular AO type C3 fractures with multiple fragments frequently require a two-step procedure with primary closed realignment, an external fixator spanning the joint, and subsequent extensive diagnostic examinations to ascertain any concomitant injuries and allow a decision on the definitive treatment that is most suitable for the type of injury present.

[Salvage operations and their differential indication for the distal radioulnar joint]

The most common cause of an arthritically damaged distal radioulnar joint is a malunion of a distal radius fracture. Therapeutically, ulnar head resection, hemiresection-interposition-technique, Kapandji-Sauvé procedure and implantation of an ulnar head prosthesis have been described. None of these procedures is able to restore the complete function of the joint. Therefore, anatomical reconstruction of the joint in acute or secondary correction osteotomy for malunited fractures of the distal radius should be performed to avoid the development of the arthrosis. Numerous clinical studies have demonstrated a similar reduction of the clinical symptoms for all procedures. Therefore, classification of the different procedures has to consider the number of complications. Biomechanically, partial resection of the distal ulna will destabilize the distal radioulnar context and clinically may lead to painful radioulnar and/or dorsopalmar instability of the distal ulnar stump. Biomechanically and clinically, this complication, next to secondary extensor tendon ruptures, has to be expected far more often following complete resection of the ulnar head than in the alternative procedures. We do not see any remaining indication for complete resection of the ulnar head. Clinical results and the occurrence of painful instability of the distal ulnar stump have been reported almost identically for the hemiresection-interposition technique and the Kapandji Sauvé procedure. Therefore, both procedures appear to be equally suitable for the treatment of painful arthrosis of the distal radioulnar joint. In patients with a preexisting instability of the distal radioulnar joint, or a major deformity of the radius or the ulna, we prefer to perform the hemiresection-interposition-technique. In these conditions we consider the remaining contact of the triangular fibrocartilage complex with the distal end of the ulna a biomechanical advantage to reduce the risk of secondary instability. Biomechanically as well as clinically, replacement of the ulnar head using a prosthesis has been shown to either avoid or solve the problem of instability. We therefore consider ulnar head replacement the treatment of choice in secondary painful instability following resection procedures at the distal end of the ulna. Primary ulnar head replacement should be considered in special indications until long-term follow-up results are available.

CT virtual reality in the preoperative workup of malunited distal radius fractures: preliminary results

Our objective was to evaluate the usefulness of CT virtual preoperative planning in the surgical repositioning of malunited distal radius fracture. Eleven patients with malunited distal radius fracture underwent multislice CT of both wrists. A preoperative workup was performed in a virtual reality environment created from the CT data sets. Virtual planning comprised three main procedures, carrying out the virtual osteotomy of the radius, prediction of the final position of the distal radius after osteotomy and computer-assisted manufacturing of a repositioning device, which was later placed at the surgical osteotomy site to reposition objectively the distal radius fragment before fixation with the osteosynthesis. All patients tolerated the surgical procedure well. During surgery, the orthopedic surgeons were not required in any of the cases to alter the position of the distal radius that was determined by the repositioning device. At postoperative follow-up, the anatomic relationship of the distal radius was restored (radial inclination, 21.4 degrees ; volar tilt, 10.3 degrees ; ulnar variance, 0.5 mm). Clinically, a significant improvement of pronation (P=0.012), supination (P=0.01), flexion (P=0.001) and extension (P=0.006) was achieved. Pain decreased from 54 to 7 points. CT virtual reality is a valuable adjunct for the preoperative workup and surgical reposition of malunited distal radius fractures.

Rotational deformity in malunited fractures of the distal radius

PURPOSE

To evaluate rotational deformity in malunited fractures of the distal radius and its effect on forearm rotation.

METHODS

Thirty-seven patients with a symptomatic malunion of the distal radius (25 with dorsal angulation and 12 with volar angulation) were assessed for rotational deformity of the distal fragment. Spiral computed tomographic scans were taken of both wrists. Rotational deformity was evaluated by comparing the radial torsion angle of the injured and uninjured sides according to Frahm. Multivariable regression analyses were used to identify the radiologic parameter that had the most important influence on forearm rotation.

RESULTS

Of the 37 patients, 23 showed a rotational deformity of the distal radius. In both dorsally and volarly angulated malunions, pronation and supination deformities were identified. There was a tendency toward more pronation deformities with volar malunion. Volar angulated malunion with a rotational deformity of less than 10 degrees showed the smallest amount of forearm supination. Losses of pronation-supination did not correlate with the amount of rotational deformity.

CONCLUSIONS

This study showed that rotational deformity is common with angulated malunions of the distal radius. The effect on forearm rotation should not be overestimated. Pretreatment computed tomographic scanning of both wrists to identify and measure malrotation of the distal radius may be helpful to improve the outcome after corrective osteotomy.

Sliding osteotomy for deformity correction following malunion of volarly displaced distal radial fractures

OBJECTIVE

To determine the outcome after a sliding osteotomy for deformity correction following malunion of volarly displaced distal radius fractures.

DESIGN

Retrospective review of a consecutive patient series.

SETTING

A university-affiliated, tertiary-care center.

PATIENTS/INTERVENTION

Ten patients with symptomatic distal radius malunion following a volarly displaced distal radial fracture (Smith's fracture) were treated with an oblique sliding osteotomy and plate fixation, through a volar approach, without using an iliac crest bone graft. Five men and five women with an average age of 41.9 years were followed for an average of 2.7 years postoperatively.

MAIN OUTCOME MEASUREMENTS

Range of motion, grip strength, Fernandez wrist score, radiographic parameters.

RESULTS

At latest follow-up, wrist extension improved from an average of 37 degrees preoperatively to 70 degrees postoperatively (P = 0.002), wrist flexion improved from an average of 40 degrees to 65 degrees (P = 0.012), and supination improved from an average of 31 degrees to 68 degrees (P = 0.002). Postoperative radiographs revealed an average deformity correction of 10.6 degrees of volar tilt, 7.7 degrees of radial inclination, 5.8 mm of ulnar variance, and 10.4 mm of volar translation. Using the Fernandez point score (0-20) system, the average overall score improved from 10.5 preoperatively to 17.6 postoperatively (P = 0.0001). Functional outcome was rated as excellent or good in 9 of 10 patients and fair in 1 patient (who experienced residual problems due to persistent ulnar-sided pain). There were two reoperations (one hardware removal, one distal ulnar hemiresection).

CONCLUSIONS

This method reliably restores distal radial anatomy, decreases pain, and improves supination without requiring iliac crest bone grafting.

Three-dimensional in vivo kinematics of the distal radioulnar joint in malunited distal radius fractures

How malunion of the distal radius affects the kinematics of the distal radioulnar joint in vivo was evaluated. A novel computed tomography image-based technique was used to quantify radioulnar motion in both wrists of 9 patients who had unilateral malunited distal radius fractures. In the injured wrists dorsal angulation averaged 21 degrees +/- 6 degrees, radial inclination averaged 18 degrees +/- 5 degrees, and radial shortening averaged 21 +/- 3 mm. Clinically, the average range of motion of the injured wrists was 75 degrees +/- 25 degrees pronation and 73 degrees +/- 23 degrees supination. Kinematics of the radius during pronation and supination in the malunited forearms was indistinguishable from that in the uninjured forearms. In both the axis of rotation of the radius passed through the center of the ulnar head, although it shifted slightly ulnar and volar in supination and radial and dorsal during pronation. In contrast to previous in vitro biomechanical findings, there was no dorsovolar radial translation at the extremes of pronation or supination and no translation of the radius along the rotation axis. Soft tissues may play a larger role in limiting function than previously appreciated, and treatment may require correction of altered soft tissue structures as well as any abnormal bone anatomy.

Functional limitation immediately after cast immobilization and closed reduction of distal radius fractures: preliminary report

The majority of research on distal radius fractures consists of retrospective, descriptive studies of patients with unstable fractures requiring fixation. The purpose of this investigation was to report on impairments in flexibility, grip strength, and motor control and on the presence of swelling and atrophy immediately after cast immobilization of closed reductions of simple distal radius fractures. Sixteen adult subjects from Kaiser Permanente Medical Center, San Francisco, entered the study, and 13 completed it. At the initial evaluation, upper extremity ranges of motion, grip strength, forearm circumferences, two-point discrimination, and motor reaction times were measured on the uninvolved side. The same measurements were taken on the affected side within 48 hours after cast removal. All but one subject worked throughout the casting period. There were significant postcasting impairments in forearm rotation (40% deficit in pronation and supination); wrist flexion, extension, and radial and ulnar deviation (50% reduction in all motions); grip strength (-32 kg, or approximately 24% of the strength of the unaffected side); and forearm circumference (-1.1 cm) and wrist circumference (+1.5 cm). Patients complained of awkwardness of the involved hand. These measured impairments immediately after immobilization of simple radius fractures were greater than the reported impairments in patients after reduction of radius fractures with fixation 6 to 27 months after injury. To prevent long-term disability and recover flexibility, strength, and function, patients with simple distal radius fractures should be referred to a hand, occupational, or physical therapist for evaluation, education, and treatment after immobilization. Longitudinal studies are needed to quantify long-term functional recovery with regard to the type of fracture and the degree of impairment measured immediately after casting.