Acute dislocations of the distal radioulnar joint and distal ulna fractures

Isolated volar dislocation of the distal radioulnar joint: Current concepts review and case report

Isolated volar distal radioulnar joint (DRUJ) dislocation is a rare condition with only a few cases reported in the literature. Its diagnosis is often overlooked in the acute phase, and there is no consensus in its management. We present the case of a 20-year-old male patient with an isolated volar radioulnar dislocation, together with a review of the literature. The aim is to present and summarize the acute management of this condition and propose a therapeutic algorithm.

Isolated Volar Radioulnar Joint Dislocation With Associated Ulnar Styloid Fracture

Isolated volar dislocation of the distal radioulnar joint is a rare occurrence and is commonly missed. The mechanism of injury typically involves hypersupination. True lateral radiographs are difficult to obtain as patients are usually limited with wrist pronation and supination, resulting in a high miss rate. We describe a 32-year-old male who presented to the emergency department (ED) with pain and swelling of the posteromedial aspect of the right wrist after punching a wall one hour prior to presentation. Examination revealed soft tissue tenderness and mild edema at the right distal ulna with an associated deformity, best visualized at the volar aspect of the right wrist. Active range of motion was limited with right wrist flexion and extension, secondary to pain and edema. Right wrist supination and pronation strength and range of motion were limited due to the patient's tenderness on examination. Peripheral nerve function and vascular examination were normal. Initial radiographs of the right hand, wrist, and forearm did not reveal a fracture or dislocation. A musculoskeletal computed tomography (CT) scan of the right hand and wrist revealed an avulsion fracture of the ulnar styloid with volar displacement of the ulna. Analgesia was achieved with an ultrasound-guided ulnar nerve block, and the right wrist was successfully reduced. This report highlights the difficulty in obtaining a diagnosis of an isolated volar dislocation of the distal radioulnar joint. We recommend obtaining a musculoskeletal CT scan in the setting of an inconclusive radiograph and incongruent physical examination. Analgesia can also be achieved with an ulnar nerve block under ultrasound guidance.

Acute isolated volar distal radioulnar joint dislocation: first surgery or conservative?

Isolated distal radioulnar joint (DRUJ) dislocations are referred to as dorsal or volar of neglected isolated volar DRUJ dislocation which was detected at the second dislocations concerning the position of the ulnar head in relationship to the radius. In contrast to large joint dislocations such as a shoulder dislocation, the clinical picture may mimic a simple soft tissue injury and the dislocation may be missed. In this article, we aimed to present a case presentation to the emergency department. Our patient who had no complaint other than wrist pain was diagnosed with volar dislocation on lateral radiography and closed reduction was performed in the emergency department with sedation. There was no recurrence in the follow-up and we achieved a satisfactory result with a painless and unrestricted wrist joint at six months. DRUJ and the ligaments stabilize the joint work in anatomical coordination and play an important role in forearm rotation movement. Traumatic injuries to these structures range from isolated tears to severe fractured dislocations. Isolated DRUJ dislocations are rare. Initial treatment of this injury is closed reduction, post-reduction stability is important and fixation is required in case of instability. Although surgical treatment is performed in cases that cannot be closed reduced and in the presence of instability after reduction, it is possible to obtain successful results in acute cases with closed reduction performed with sedation in emergency departments. For this reason, a conservative approach should be tried before making a surgical decision in these injuries that require special attention in diagnosis.

Isolated dorsal dislocation of the distal radioulnar joint: A case report

Isolated acute dislocation of the distal radioulnar joint is a rare lesion, and in 50 % of cases goes unrecognized; it may be palmar or dorsal. Its diagnosis is suspected when the wrist is traumatic, painful, with limited pronosupination and no fracture on radiological examination. Treatment is aimed at preventing the development of chronic instability and/or arthrosis, and consists of reduction followed by immobilization.

Higher-Than-Expected Rates of Distal Radioulnar Joint Fixation in Radial Shaft Fractures: Location of Fracture Matters

BACKGROUND

The purpose of this study was to evaluate rates of distal radioulnar joint (DRUJ) fixation based on location of the radial shaft fracture and risk factors associated with postoperative complications following radial shaft open reduction internal fixation (ORIF).

METHODS

Adult patients who underwent isolated radial shaft ORIF from 2014 to 2018 were identified from American College of Surgeons National Surgical Quality Improvement Program database and stratified by fracture location and by the presence or absence of DRUJ fixation. Preoperative patient characteristics and postoperative complications were compared to determine risk factors associated with DRUJ fixation.

RESULTS

We identified 1517 patients who underwent isolated radial shaft ORIF, of which 396 (26.1%) underwent DRUJ fixation. Preoperative patient characteristics and postoperative complications were similar between cohorts. Distal radioulnar joint fixation was performed in 50 (30.7%) of 163 distal radial shaft fractures, 191 (21.8%) of 875 midshaft fractures, and 3 (13.0%) of 23 proximal shaft fractures (P = .025). Risk factors for patients readmitted include male sex (odds ratio [OR] = 12.76, P = .009) and older age (OR = 4.99, P = .035). Risk factors for patients with any postoperative complication include dependent functional status (OR = 6.78, P = .02), older age (50-69 vs <50) (OR = 2.73, P = .05), and American Society of Anesthesiologists (ASA) ≥3 (OR = 2.45, P = .047).

CONCLUSIONS

The rate of DRUJ fixation in radial shaft ORIF exceeded previously reported rates of concomitant DRUJ injury, especially among distal radial shaft fractures. More distally located radial shaft fractures are significantly associated with higher rates of DRUJ fixation. Male sex is a risk factor for readmission, whereas dependent functional status, older age, and ASA ≥3 are risk factors for postoperative complications.

Comparative Study of 2 Bone Anchors Using a Limited Open Procedure for the Management of Distal Radioulnar Joint Instability

BACKGROUND

Arthroscopic and open surgical procedures are commonly used to repair distal radioulnar joint (DRUJ) instability. Both may result in patient dissatisfaction and recurrence of DRUJ instability. An alternative treatment that yields improved outcomes is a limited open approach using a bone anchor to support the DRUJ.

METHODS

A retrospective chart review of 58 patients (59 extremities) aged 18 to 60 years with type 1B Palmer rupture (3 months or more after injury) of the triangular fibrocartilage complex (TFCC) without distal radius fracture was conducted. Inclusion criteria are: 3 to 12 months after injury, clinical DRUJ instability, and minimum of 6 months of postoperative follow-up. Operative fixation with Stryker Sonic or Depuy Mitek anchor was done by the same surgeon using a limited open procedure. Preoperative and postoperative assessments included Disability of the Arm, Shoulder, and Hand; Brief Pain Inventory; Wong-Baker FACES Pain Rating Scale; Numeric Pain Scale; range of motion; and recurrence of instability. A multivariate analysis of variance model was fit to imputed data to assess the effect of both anchors.

RESULTS

Clinical and statistical differences were found in preoperative and postoperative assessments for either the Stryker Sonic or the Depuy Mitek anchor but not between anchor types. There was no recurrence after 3 years with either anchor.

CONCLUSION

Patients requiring TFCC repair using the Stryker Sonic or Depuy Mitek anchor experienced: (1) significant clinical and statistical improvement in postoperative assessments; (2) patient satisfaction; and (3) corrected DRUJ instability. Consequently, major determinants in deciding which bone anchor to use may be based on cost or surgeon's preference.

Operative Stabilization of Distal Radius Fractures Presenting With Ulnar Head Subluxation/Dislocation Addresses Distal Radioulnar Joint Instability Without Further Stabilization Procedures

OBJECTIVES

To determine the prevalence of ulnar head subluxation/dislocation in distal radius fracture and to discuss management, surgical outcomes, and relevant anatomy.

SETTING

Urban tertiary care hospital.

PATIENTS/PARTICIPANTS

Two hundred seventy-one patients with displaced distal radius fractures undergoing surgical management were reviewed to determine the incidence of ulnar head subluxation or dislocation using the Mino criteria defined by Mino et al.

MAIN OUTCOMES

Postoperative computed tomography and radiographs were assessed for sigmoid notch and distal radioulnar joint (DRUJ) reduction and fracture healing. Range of motion, functional limitation, and pain were documented at final outcome.

RESULTS

Of the 271 cases, there were 8 cases of prereduction DRUJ subluxation/dislocation, including 2 frank dislocations and 6 subluxations (2.95%). All were treated with open reduction and internal fixation (ORIF) of the distal radius with a volar locked plate. In addition, 1 patient underwent ORIF of an associated distal ulnar shaft fracture and another, who had a grade 1 open fracture over the distal ulna, underwent open TFCC repair. The remaining 6 patients had closed reduction of the DRUJ without further stabilizing procedures. All had stable DRUJ joints following ORIF, both intra-operatively and at final follow-up. All ulnar heads were located within the DRUJ on post-op computed tomography; using the more sensitive radioulnar ratio there was residual ulnar head subluxation in 5/8 patients. Range of motion and functional outcome were excellent at an average of 133 weeks postoperatively. The DRUJ was stable at long-term follow-up in all patients.

CONCLUSIONS

Ulnar head subluxation/dislocation is an uncommon injury in the setting of distal radius fracture. When present, it can usually be treated effectively with operative stabilization of the distal radius fracture without further stabilizing procedures.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Distal Radioulnar Joint Instability

Instability of the distal radioulnar joint is a source of ulnar-sided wrist pain and functional impairment. Symptomatic instability may present acutely, after a recent traumatic injury, or in a delayed fashion as chronic instability following a history of a traumatic event. A detailed understanding of the complex anatomy, biomechanics, and stabilizing structures of the distal radioulnar joint is important to evaluate and treat acute and chronic instability. This article describes the pathophysiology of distal radioulnar joint instability with attention to the anatomic structures involved and provides information about evaluation and treatment.

Distal Radioulnar Joint Instability and Associated Injuries: A Literature Review

The distal radioulnar joint (DRUJ) allows supination and pronation of the distal forearm and wrist, an integral motion in everyday human activity. DRUJ injury and chronic instability can be a significant source of morbidity in patients’ lives. Although often linked with distal radius fractures, DRUJ injury may occur in a variety of other upper extremity injuries, as well as an isolated pathology. Diagnosis of this injury requires the clinician to have a high index of suspicion and low threshold for clinical testing and further imaging of the DRUJ. The purpose of this article is to provide a review on DRUJ anatomy and biomechanics, to discuss common diagnostic and treatment modalities, and to identify common injuries associated with DRUJ instability.

Irreducible Chronic Volar Dislocation of the Distal Radioulnar Joint After Surgery for Distal Radius Fracture: A Case Report

CASE

We report a case of irreducible chronic volar dislocation of the distal radioulnar joint (DRUJ) after surgery for distal radius fracture. The patient underwent volar locking plate fixation for distal radius fracture. Despite the satisfactory alignment of the distal radius, irreducible volar dislocation of the DRUJ was discovered at 5 weeks after the initial surgery. DRUJ reconstruction at 9 weeks after injury using the Adams-Berger procedure resulted in a stable and functional DRUJ and wrist.

CONCLUSION

To prevent postoperative DRUJ instability or dislocation, the DRUJ should be evaluated for stability immediately after fracture fixation.

Fracture-dislocations of the forearm joint: a systematic review of the literature and a comprehensive locker-based classification system

BACKGROUND

Monteggia, Galeazzi, and Essex-Lopresti injuries are the most common types of fracture-dislocation of the forearm. Uncommon variants and rare traumatic patterns of forearm fracture-dislocations have sometimes been reported in literature. In this study we systematically review the literature to identify and classify all cases of forearm joint injury pattern according to the forearm joint and three-locker concepts.

METHODS

A comprehensive search of the PubMed database was performed based on major pathological conditions involving fracture-dislocation of the forearm. Essex-Lopresti injury, Monteggia and Galeazzi fracture-dislocations, and proximal and/or distal radioulnar joint dislocations were sought. After article retrieval, the types of forearm lesion were classified using the following numerical algorithm: proximal forearm joint 1 [including proximal radioulnar joint (PRUJ) dislocation with or without radial head fractures], middle radioulnar joint 2, if concomitant radial fracture R, if concomitant interosseous membrane rupture I, if concomitant ulnar fracture U, and distal radioulnar joint 3 [including distal radioulnar joint (DRUJ) dislocation with or without distal radial fractures].

RESULTS

Eighty hundred eighty-four articles were identified through PubMed, and after bibliographic research, duplication removal, and study screening, 462 articles were selected. According to exclusion criteria, 44 full-text articles describing atypical forearm fracture-dislocation were included. Three historical reviews were added separately to the process. We detected rare patterns of two-locker injuries, sometimes referred to using improper terms of variant or equivalent types of Monteggia and Galeazzi injuries. Furthermore, we identified a group of three-locker injuries, other than Essex-Lopresti, associated with ulnar and/or radial shaft fracture causing longitudinal instability. In addition to fracture-dislocations commonly referred to using historical eponyms (Monteggia, Galeazzi, and Essex-Lopresti), our classification system, to the best of the authors' knowledge, allowed us to include all types of dislocation and fracture-dislocation of the forearm joint reported in literature. According to this classification, and similarly to that of the elbow, we could distinguish between simple dislocations and complex dislocations (fracture-dislocations) of the forearm joint.

CONCLUSIONS

All injury patterns may be previously identified using an alphanumeric code. This might avoid confusion in forearm fracture-dislocations nomenclature and help surgeons with detection of lesions, guiding surgical treatment.

LEVEL OF EVIDENCE

V.

Acute Distal Radioulnar Joint Instability: Evaluation and Treatment

This article reviews the anatomy and mechanics of pronation and supination (axial rotation) of the forearm through the distal radioulnar joint (DRUJ), and the proximal radioulnar joint (PRUJ). Injuries to the bones and/or ligaments of the forearm, wrist, or elbow can result in instability, pain, and limited rotation. Acute dislocations of the DRUJ commonly occur along with a fracture to the distal radius, radial metadiaphysis, or radial head. These injuries are all caused by high-energy trauma. Outcomes are predicated on anatomic reduction and restoration of stability to the DRUJ and PRUJ with or without ligamentous repair or reconstruction.

Isolated dorsal dislocation of the distal radioulnar joint: A case report

Isolated distal radioulnar joint (DRUJ) dislocation is a rare injury. Reports of isolated DRUJ luxations, volar or dorsal, are often case reports and rarely a series of cases. We present a case of an isolated acute dorsal dislocation of the distal radioulnar joint in a 25-year-old man. The patient underwent closed reduction and a transcutaneous radioulnar pinning was done followed by cast immobilization in neutral rotation during 6 weeks. After six months follow -up, the functional result was satisfactory, patient experienced no pain and had no restrictions in work or sports-related activities.

Screw Fixation and Autogenous Bone Graft for an Irreducible Distal Ulna Fracture Associated with Distal Radius Fracture

Distal ulna fractures often occur with distal radius fractures, and their treatment method is still controversial. We considered reduction of the distal radio-ulnar joint (DRUJ) surface the most important factor when treating distal ulna fractures accompanied by residual dislocation. We herein presented a patient with a distal ulna fracture accompanied by dislocation of the DRUJ surface in whom an autogenous bone fragment collected from the radius was grafted onto the ulnar bone defect after open reduction and Herbert screw fixation. In this technique, the bone fragment was supported through the medullary cavity by inserting a Herbert screw, which was less likely to cause irritation between the screw and surrounding tissue, because the screw was almost entirely present in the bone. In addition, an autogenous bone graft from the same surgical field may be less invasive than that from another region.

Radial shaft fracture obliquity as a predictor of distal radioulnar joint instability

We assessed whether radial shaft fracture obliquity measurements on radiographs could predict intra-operative distal radioulnar joint instability. We also clinically validated previously described predictors of distal radioulnar joint instability, which included a fracture line within 7.5 cm of the lunate fossa, radial shortening >5 mm, and ulna styloid fracture. We retrospectively analysed the radiographs of all surgically managed patients in our unit with radial shaft fractures from 2006 through 2016. The degree of obliquity was analysed on the basis of the maximum fracture-line angle in either the coronal or the sagittal plane. A radial shaft fracture obliquity >30° is predictive of distal radioulnar joint instability ( P = 0.001). Radial fracture shaft obliquity >30° was the most sensitive radiological parameter (76%) for predicting distal radioulnar joint instability. Oblique radial shaft fractures appear to be associated with increased incidence of distal radioulnar joint instability. This radiologic parameter may be used together with established parameters in predicting distal radioulnar joint instability for surgical treatment.

LEVEL OF EVIDENCE

III.

Technique for Intramedullary Stabilization of Ulnar Neck Fractures

BACKGROUND

Distal ulna fractures at the ulnar neck can be seen in association with distal radius fractures, and multiple techniques have been described to address the ulnar neck component of these injuries. We have found that treatment of ulnar neck fractures can be challenging in terms of anatomy and fracture fixation. We present a new percutaneous fixation technique for ulnar neck fractures commonly seen with distal radius fractures.

TECHNIQUE

Fixation of the ulnar neck fracture is performed after fixation of the distal radius fracture. Our technique uses anterograde intramedullary fixation to stabilize the fracture with a 1.6-mm (0.062 inch) Kirschner wire or a commercially available metacarpal fixation intramedullary nail. The fixation is introduced into the intramedullary space of the ulnar shaft 4 to 6 cm proximal to the fracture at a separate surgical site along the subcutaneous border of the ulna. The fixation is also supported with a sugar-tong splint for the first few weeks after surgery and requires removal of the ulnar implant approximately 10 weeks after implantation.

CONCLUSION

Our technique utilizes a percutaneous approach with minimal fracture exposure. It provides a relatively simple and reproducible method to address ulnar neck fractures commonly seen in association with distal radial fractures.

The "second ulnar groove", a MRI sign suggesting a previous palmar luxation of the ulna at the distal radioulnar joint

INTRODUCTION

A cortical lined impaction on the radiodorsal side of the ulnar head may be at the origin of a "second ulnar groove" (SUG). The goal of this article is to illustrate this MRI sign, prompting for further investigation of the distal radioulnar joint (DRUJ). Hence associated soft tissue pathology may be detected, which may lead to instability.

MATERIAL AND METHODS

Following an anterior luxation of the ulna at the DRUJ a second cortical lined groove in a previously normal distal ulna was discovered. A data base review from January 2008 to August 2016 of the axial FS PD-TSE WI 1.5T MRI views of 1.716 patients was accomplished in search of similar bone defects.

RESULTS

Eight patients with previous severe wrist trauma presented with a similar posttraumatic ulnar bone defect. The preceding anterior luxation at the DRUJ was only clearly demonstrated in five patients. However, two more patients had a residual anterior subluxation. Different imaging techniques are discussed and the differential diagnosis is well illustrated.

CONCLUSIONS

The type of trauma, the specific location and the morphology of a second ulnar groove, all compatible with a sequel of an anterior luxation of the ulna at the DRUJ, should lead to a further specific clinical and MRI revaluation of the DRUJ.

Volar Distal Radioulnar Joint Dislocation Associated with Acute Median Nerve Neuropathy and a Distal Radius Fracture

Volar distal radioulnar (DRUJ) dislocations are uncommon and can easily be missed. We present a rare case of an irreducible volar DRUJ dislocation associated with a distal radius fracture and acute median nerve neuropathy at the wrist. An attempt to reduce the DRUJ dislocation in the emergency department had failed. The patient was then taken to the operating room requiring a carpal tunnel release, as well as an open reduction and internal fixation of the distal radius fracture and repair of the volar distal radioulnar ligament. We also review some of the volar DRUJ case reports in the literature.

Subtle radiographic findings of acute, isolated distal radioulnar joint dislocation

Distal radioulnar dislocations typically occur in association with fractures of the distal radius and/or ulna. Rare isolated dislocations or subluxations are more difficult to diagnose and are initially missed in up to 50 % of cases. We present two cases of missed isolated volar rotatory dislocation of the distal radioulnar joint. Subtle, overlooked radiographic findings of abnormal radioulnar alignment and ulnar styloid projection are highlighted. The supplemental role of cross-sectional imaging is reviewed. Adequate clinical information, appropriate radiographic technique, and high index of suspicion are necessary for the accurate and timely diagnosis of this rare injury pattern.

Distal Radioulnar Joint Instability

Distal radioulnar joint (DRUJ) instability is a common clinical condition but a frequently missed diagnosis. Both surgical and nonsurgical treatments are possible for chronic cases of DRUJ instability. Nonsurgical treatment can be considered as the primary therapy in less active patients, while surgery should be considered to recover bone and ligament injuries if nonsurgical treatment fails to restore forearm stability and function. The appropriate choice of treatment depends on the individual patient and specific derangement of the DRUJ.

What's in a name? Upper extremity fracture eponyms (Part 1)

Eponymous extremity fractures are commonly encountered in the emergency setting. Correct eponym usage allows rapid, succinct communication of complex injuries. We will review both common and less frequently encountered extremity fracture eponyms, focusing on imaging features to identify and differentiate these injuries. We focus on plain radiographic findings, with supporting computed tomography (CT) images. For each injury, important radiologic descriptors are discussed which may need to be communicated to consultants. Aspects of management and follow-up imaging recommendations are included. This is a two-part review: Part 1 focuses on fracture eponyms of the upper extremity, while Part 2 covers fracture eponyms of the lower extremity.

A rare combination: locked volar distal radio-ulnar joint dislocation with isolated volar capsule rupture

Distal Radioulnar Joint (DRUJ) dislocation is a commonly missed injury. A high clinical suspicion is required as the dislocation may not be obvious in the conventional views of radiographs. Volar DRUJ dislocations are far less common than the dorsal ones. Since triangular fibrocartilage complex (TFCC) is the major stabilizer of DRUJ, it is common that the irreducible DRUJ dislocation is associated with TFCC tear. We report a patient who had irreducible volar DRUJ dislocation blocked by the volar lip of sigmoid notch, with only isolated volar capsule rupture.

Emergency department evaluation and treatment of wrist injuries

Correct diagnosis of wrist injuries is critical in preventing prolonged pain and dysfunction. Radiographs cannot diagnose a large percentage of injuries. Wrist sprain is considered one of the most common yet most treacherous emergency department (ED) diagnoses because radiographs do not always rule out all acute injuries. Knowledge of the anatomy, normal physical examination findings, and physical examination abnormalities associated with different pathological conditions, is paramount in making the correct diagnosis. This article focuses on the anatomy, diagnosis, and ED management of acute wrist injuries, including fractures and dislocations.

Disorders of the distal radioulnar joint

The distal radioulnar joint is responsible for stable forearm rotation. Injury to this joint can occur following a variety of mechanisms, including wrist fractures, ligamentous damage, or degenerative wear. Accurate diagnosis requires a clear understanding of the anatomy and mechanics of the ulnar aspect of the wrist. Injuries can be divided into three major categories for diagnostic purposes, and these include pain without joint instability, pain with joint instability, and joint arthritis. New advancements in imaging and surgical technique can allow for earlier detection of injuries, potentially preserving joint function. In this article, the authors review the pertinent anatomy, biomechanics, and major abnormality involving the distal radioulnar joint.

LCP distal ulna plate fixation of irreducible or unstable distal ulna fractures associated with distal radius fracture

PURPOSE

The advent of locking compression plate (LCP) has provided convenient and secure fixation of distal ulna fractures. This study was performed to evaluate the functional and clinical outcomes following LCP distal ulna plate fixation of irreducible or unstable distal ulna fractures with concomitant distal radius fractures.

METHODS

Retrospective review of 17 patients who had been treated with LCP distal ulna plates for distal ulna fractures was performed. The average age of the patients was 58.9 years (range 21-87 years), and the mean follow-up period was 15 months (range 12-20 months). This study consisted of eleven fractures involving metaphysis and six ulna styloid base fractures. Fracture union, radiologic parameters, stability of the distal radioulnar joint (DRUJ), and functional outcomes, including ROM, grip strength, and functional scores were evaluated.

RESULTS

All patients showed bony union, the average radial height was 10.5 mm, and the ulnar variance was 0.8 mm on final radiographs. None of the patients had instability of the DRUJ compared with the opposite wrist, and the subluxation ratio was within normal range on the follow-up CT scan. There were 6 excellent and 11 good cases according to Sarmiento's modified wrist score at the last follow-up.

CONCLUSIONS

Locking compression plate distal ulna plate fixation of irreducible or unstable distal ulna fractures after stabilization of concomitant distal radius fractures showed favorable results in union, alignment, and functional outcomes and therefore could be one of the recommendable implant options for distal ulna fractures.

Distal ulna hook plate fixation for unstable distal ulna fracture associated with distal radius fracture

The significance of distal ulna fractures is often undermined, which can result in inadequate treatment compared with fractures of the radius, the ulna's larger counterpart. However, little guidance exists in the current literature on how to manage distal ulna head or neck fractures and intra-articular ulna head fractures. Therefore, the purpose of this retrospective study was to evaluate the outcomes of distal ulna hook plate fixation for the treatment of an unstable distal ulna fracture associated with a distal radius fracture. Twenty-five patients with unstable distal ulna fractures who underwent stable fixation for an associated distal radius fracture were included in the study. All patients achieved satisfactory reduction and bony union. Average final motion was as follows: wrist flexion, 72° (range, 60°-85°); extension, 69° (range, 65°-80°); pronation, 77° (range, 55°-95°); supination, 82° (range, 65°-90°); ulnar deviation, 35° (range, 15°-50°); and radial deviation, 24° (range, 10°-40°). Average postoperative grip strength was 28 kg (range, 22-30 kg) and was 91% (range, 71%-100%) in the cases in which the dominant hand was injured and 80% (range, 65%-100%) in the cases in which the nondominant hand was injured. Average postoperative modified Mayo wrist score and Disabilities of the Arm, Shoulder and Hand score was 87 points (range, 65-100 points) and 14 points (range, 0-54 points), respectively. Chronic instability of the distal radioulnar joint was not encountered in any patient. Thus, the study demonstrated that distal ulna hook plate fixation for the treatment of unstable distal ulna fractures can achieve healing with good alignment, satisfactory function, and minimal transient morbidity.

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.

Galeazzi fracture

Galeazzi fracture is a fracture of the radial diaphysis with disruption at the distal radioulnar joint (DRUJ). Typically, the mechanism of injury is forceful axial loading and torsion of the forearm. Diagnosis is established on radiographic evaluation. Underdiagnosis is common because disruption of the ligamentous restraints of the DRUJ may be overlooked. Nonsurgical management with anatomic reduction and immobilization in a long-arm cast has been successful in children. In adults, nonsurgical treatment typically fails because of deforming forces acting on the distal radius and DRUJ. Open reduction and internal fixation is the preferred surgical option. Anatomic reduction and rigid fixation should be followed by intraoperative assessment of the DRUJ. Further intraoperative interventions are based on the reducibility and postreduction stability of the DRUJ. Misdiagnosis or inadequate management of Galeazzi fracture may result in disabling complications, such as DRUJ instability, malunion, limited forearm range of motion, chronic wrist pain, and osteoarthritis.