Morphological evaluation of the distal interosseous membrane using ultrasound

The Distal Oblique Bundle in the Distal Forearm: From Anatomical Features to Clinical Implementation

Background and objective The distal oblique bundle (DOB) is nowadays recognized as the thickest component of the distal interosseous membrane (DIOM). It is neither thought to be a clear-cut ligament, and nor does it follow the typical configuration of the rest of the DIOM. It is not always present and some studies have raised disputes about its prevalence and a few anatomical features. In this study, we aimed to provide data on the prevalence and anatomical features of the DOB, which are of great importance at this early stage of research into the topic. Our findings have been correlated with current knowledge and are expected to contribute to clinical implementation. Materials and methods Twenty-eight fresh-frozen forearms were utilized for measurements. Specifically, mean length, width, distance from the middle of the bundle's insertion to the ulna to the tip of the styloid process of the ulna, as well as the distance from the midpoint of its insertion to the radius to the tip of the radiuses' styloid process were calculated. The prevalence was described with a cutoff thickness point of 0.5 mm. Early results based on three cases of DOB reconstruction with the "Riggenbach" technique due to distal radioulnar joint (DRUJ) instability were documented. Results Eleven DOBs were reported out of the 28 specimens, suggesting a prevalence of 39.3%. The mean thickness was 0.88 mm (range: 0.6-1.3 mm), the mean width was 5.22 mm (range: 2.2-8.4 mm), and the mean length was 25.68 mm (range: 22.7-29.2 mm). Proximally, the mean distance from the bundle's ulnar insertion to the tip of the styloid process of the ulna was 51.02 mm (range: 45.5-55.6 mm) while distally, the mean distance from the bundle's insertion to the radius to the tip of the styloid process of the radius was 34.5 mm (range: 31.3-37.7 mm). After a follow-up of at least six months, improvement was evident in all measured areas in the three patients who underwent surgery. Additionally, they reported satisfaction and accomplishment of their preoperative goals. Conclusions Discrepancies in measurements in some anatomic features between studies are probably due to variations in specimen types, measurement methods, and sites. Efforts must continue to be made on a more extensive scale and in a more standardized manner for more factual results and conclusions. "Reconstruction-recreation" or "original construction-creation" procedures yield promising results in a fast, simple, and less invasive manner than traditional methods of DRUJ stabilization.

Stabilization of the Distal Radioulnar Joint Using the TightRope Implant: A Distal Oblique Bundle Augmentation

Background  Triangular fibrocartilage complex (TFCC) injury often results in distal radioulnar joint (DRUJ) instability. However, not all patients with a ruptured TFCC have an unstable DRUJ as in these patients a distal oblique bundle (DOB) may be present. We assumed that augmentation of the DOB leads to a more stable situation following reinsertion of the TFCC. We present the clinical results of a new surgical technique using the TightRope system as a DOB augmentation. Description of Technique  All cases were treated under regional anesthesia with the TightRope implant for which a tunnel was drilled from the distal ulna through the radius along the path of the DOB. The TightRope was passed through the tunnel and secured with buttons on either side. X-rays were made during surgery to confirm correct positioning. Methods  A retrospective study was performed analyzing 21 cases treated with a TightRope augmentation of the DOB. The primary outcome was measured using the patient-rated wrist evaluation (PRWE) score at least 12 months after surgery. Results  Postoperatively, the DRUJ was stable in all patients. The median PRWE score was 16 for the injured side compared to zero for the uninjured side ( p -value: < 0.001). The median pronation and supination were not statistically significant when we compared the injured side to the uninjured side. The median grip strength was 31 kg for the injured side compared to 38 kg for the uninjured side ( p -value: 0.015). There were two minor postoperative complications (10%). Conclusion  This technique is capable of restoring DRUJ stability with a short immobilization period resulting in good patient-related outcomes and a low complication rate.

Does surgical reconstruction of the distal oblique bundle (DOB) provide similar stability as the intact bundle or Adams procedure? A systematic review

INTRODUCTION

The aim of this review was to summarize the available evidence for biomechanical stability following surgical DOB reconstruction, and to determine whether distal radioulnar joint (DRUJ) stability with a reconstructed DOB was similar to the native intact condition or that after the Adams procedure.

MATERIAL AND METHODS

A systematic literature search according to the PRISMA guidelines was performed using the databases PubMed and Embase. The following search algorithm was used: ("DOB" OR "Distal Oblique Bundle") AND "Reconstruction". Biomechanical or human cadaveric studies that measured stability of the DRUJ after reconstruction of the DOB were included.

RESULTS

Four articles were included in the final analysis. DOB incidence was reported to be between 50% and 70%. Two studies observed no differences between the intact situation and the reconstructed DOB, respectively the Adams procedure. A further author group found no signs of major instability after the Adams reconstruction or after DOB reconstruction, except for decreased stability during supination in the DOB sample. In another study, similar results could be shown for the Adams and DOB reconstruction groups; however, the DOB sample showed decreased dorsal translation of the radius during forearm supination.

CONCLUSION

In conclusion, DOB reconstruction was proven to stabilize the DRUJ adequately. Moreover, the reconstructed DOB showed the same stability as the native DOB, except for one study, in which stability following reconstruction was reduced during supination. No significant difference between the DOB and the Adams reconstruction could be observed.

Interdisciplinary consensus statements on imaging of DRUJ instability and TFCC injuries

OBJECTIVES

The purpose of this agreement was to establish evidence-based consensus statements on imaging of distal radioulnar joint (DRUJ) instability and triangular fibrocartilage complex (TFCC) injuries by an expert group using the Delphi technique.

METHODS

Nineteen hand surgeons developed a preliminary list of questions on DRUJ instability and TFCC injuries. Radiologists created statements based on the literature and the authors' clinical experience. Questions and statements were revised during three iterative Delphi rounds. Delphi panelists consisted of twenty-seven musculoskeletal radiologists. The panelists scored their degree of agreement to each statement on an 11-item numeric scale. Scores of "0," "5," and "10" reflected complete disagreement, indeterminate agreement, and complete agreement, respectively. Group consensus was defined as a score of "8" or higher for 80% or more of the panelists.

RESULTS

Three of fourteen statements achieved group consensus in the first Delphi round and ten statements achieved group consensus in the second Delphi round. The third and final Delphi round was limited to the one question that did not achieve group consensus in the previous rounds.

CONCLUSIONS

Delphi-based agreements suggest that CT with static axial slices in neutral rotation, pronation, and supination is the most useful and accurate imaging technique for the work-up of DRUJ instability. MRI is the most valuable technique in the diagnosis of TFCC lesions. The main indication for MR arthrography and CT arthrography are Palmer 1B foveal lesions of the TFCC.

CLINICAL RELEVANCE STATEMENT

MRI is the method of choice for assessing TFCC lesions, with higher accuracy for central than peripheral abnormalities. The main indication for MR arthrography is the evaluation of TFCC foveal insertion lesions and peripheral non-Palmer injuries.

KEY POINTS

• Conventional radiography should be the initial imaging technique in the assessment of DRUJ instability. CT with static axial slices in neutral rotation, pronation, and supination is the most accurate method for evaluating DRUJ instability. • MRI is the most useful technique in diagnosing soft-tissue injuries causing DRUJ instability, especially TFCC lesions. • The main indications for MR arthrography and CT arthrography are foveal lesions of the TFCC.

Distal radioulnar joint instability: Diagnosis and treatment of acute and chronic lesions

Distal radioulnar joint instability is a common clinical condition that can be either acute or chronic. Its management requires extensive knowledge of all the anatomical structures around the wrist area. The clinical examination must identify all damaged structures in order to define a customized reconstruction strategy. The aim of treatment is to prevent the development of chronic instability and/or arthritic lesions, which can only be treated with palliative surgery. Distal radioulnar instability is complex. Its management shares similarities with that of knee instability, with a wide range of conditions ranging from a sprain with isolated ligament tear to complex dislocation in which multiple ligaments are torn. In particular, the triangular fibrocartilage complex, which is a pillar of distal radioulnar joint stability, is not the sole stabilizer of this joint. The treatment strategy is not as simple as just reattaching this ligament to treat all of the acute and chronic clinical signs. The goal of the present study is to describe the various structures and possible lesions in this joint and then how to repair them. The diagnostic and therapeutic difficulties justify treatment at a specialized center.

Optimizing the Orientation of a Suture Button to Stabilize the Distal Radioulnar Joint in a Sawbones Model

Purpose

When left untreated, distal radioulnar joint (DRUJ) instability leads to prolonged wrist pain and weakness during pronosupination. Current treatment options are technically demanding and result in mixed outcomes. This study used a synthetic bone model to evaluate the potential of using a suture button to stabilize the DRUJ and find its optimal configuration.

Methods

A suture button was placed between the radius and ulna of a synthetic bone model with DRUJ instability. The suture button was placed straight across or in an oblique orientation while the forearm was in 60° of pronation, neutral, or 60° of supination for 6 configurations. The range of motion, dislocation events, dorsal translation, volar translation, and gaps between the radius and ulna were measured and compared among these 6 configurations.

Results

Full range of motion (ROM) was achieved in all configurations except for suture buttons placed while the forearm was in 60 ° pronation. Obliquely placed suture buttons led to more dislocations than straight across suture buttons. The 2 configurations that offered full ROM with the greatest stability were straight across 60° supination and straight across neutral configuration, with the supinated configuration slightly improving stability.

Conclusions

In this model, suture buttons restored DRUJ stability while maintaining full ROM, indicating that suture buttons have the potential to be used as a treatment option for stabilization of DRUJ. The optimal configuration of a suture button is likely in the straight across 60° supinated configuration, as it provides the greatest stability without sacrificing ROM compared with the other suture button configurations.

Clinical relevance

Additional treatment options for the stabilization of DRUJ are needed. Suture buttons may be of use.

Clinical relationship between distal interosseous membrane thickness measured through magnetic resonance imaging and distal radioulnar joint stability: A retrospective study

BACKGROUND

Cadaveric studies suggest that a thick part of the distal interosseous membrane (DIOM), known as the distal oblique bundle (DOB), contributes to the distal radioulnar joint (DRUJ)'s stability. We hypothesized that the DIOM thickness, measured through magnetic resonance imaging (MRI), has a clinically significant association with DRUJ stability.

METHODS

We retrospectively reviewed patients, from February 2018 to April 2019, who underwent wrist MRI examination with physical examination for DRUJ stability. We evaluated the correlation between their MRI findings (i.e., triangular fibrocartilage complex [TFCC] tears and presence of the DOB) and DRUJ instability.

RESULTS

Out of 85 patients with an average age of 42 years, 45 (53%) had foveal TFCC tears, 29 (34%) had a DOB, and 38 patients (45%) had clinical DRUJ instability. Patients with DRUJ instability had a significantly higher incidence of foveal TFCC tears (30/38, vs 15/47, p < 0.001), while DOB was absent (36/38 vs. 20/47, p < 0.001). Among 45 patients with foveal TFCC tears, only 1 out of 13 patients with a DOB had DRUJ instability, whereas 29 out of 32 patients without a DOB had DRUJ instability (p < 0.001). The odds ratio for DRUJ instability was 11.7 (95% CI 2.9-47.5, p = 0.001) for foveal TFCC tear and 54.2 (95% CI 8.2-358.2, p < 0.001) for the absent DOB.

CONCLUSIONS

Clinical DRUJ instability was less common when the DOB is present in patients with foveal TFCC tears, which supports DOB's role as a secondary DRUJ stabilizer.

Combined simple elbow dislocation and forearm joint injuries. A systematic review of the literature with injury patterns and current treatment rationale

INTRODUCTION

Recent studies have allowed a great improvement in understanding elbow and forearm traumatic injuries. Simple elbow dislocations combined with forearm injuries have been occasionally reported in the literature. The aim of this study was to detect the possible patterns of simple elbow dislocations and forearm fracture-dislocations, providing a classification scheme to guide surgical treatment.

MATERIALS AND METHODS

PubMed search was performed to find combination of simple elbow dislocation and forearm joint injury, between 2000 and 2020, including clinical studies and case report. All articles related to pediatric patient or with complex elbow dislocation were excluded. After identification, articles were analyzed for the description of injury patterns reported according to locker-based classification system of forearm joint injuries.

RESULTS

Finally, 15 articles were included. Most of the patients sustained high-energy trauma. According to locker-based classification system, simple elbow dislocation was combined with: MRUJ and DRUJ Galeazzi injury (2IR.3), PRUJ and MRUJ injury (1.2I), PRUJ and MRUJ injury with radial shaft fracture (1.2IR), PRUJ and MRUJ injury with ulnar shaft fracture (1.2 IU), PRUJ and MRUJ injury with radial and ulnar shaft fracture (1.2IRU), PRUJ MRUJ DRUJ Essex-Lopresti injury (1.2I.3), and PRUJ MRUJ DRUJ injury with radial shaft fracture (1.2IR.3). Thirteen out of 15 patients undergo surgical treatment. Clinical results were overall favorable.

CONCLUSIONS

Simple elbow dislocation combined with forearm joint injury is an uncommon traumatic pattern usually secondary to high-energy trauma. A thorough knowledge of elbow and forearm biomechanics, and classification of anatomical lesion is mandatory for a successful treatment.

Stabilization of the distal radioulnar joint by reconstructing the interosseous membrane's distal oblique bundle: Cadaver study

INTRODUCTION

The distal radioulnar (DRU) ligaments play a key role in stabilizing the DRU joint. Ligament reconstruction in this area is an accepted treatment. However, another structure may also be a significant DRUJ stabilizer-the distal oblique bundle (DOB) of the interosseous membrane (IOM). Recent studies have described DOB reconstruction methods, which should be compared to DRU ligament reconstruction.

METHODS

Twelve upper limbs were used. First, a descriptive anatomy study was done to determine the prevalence and features of the DOB (insertions, thickness, and relationship with DRU ligaments). Second, biomechanical testing was done with the wrist in neutral position, supination, and pronation. Distal radius translation was evaluated first on an intact wrist then evaluated again after creating bidirectional instability. Lastly, the same tests were repeated after DRU reconstruction using the Adams-Berger technique and DOB reconstruction using the Riggenbach technique.

RESULTS

The DOB was present in 50% of specimens and was bilateral. Reconstructing the DOB stabilized the wrist to the same degree as the Adams-Berger technique in neutral and pronation (8% residual major instability). Stability was harder to achieve in supination (25% major instability). It was better at controlling posterior radial translation than anterior translation (3% versus 14% major instability).

CONCLUSION

DOB reconstruction appears to be a reliable and less invasive treatment option for DRUJ instability since it is extra-articular. However, the wrist's position and the direction of radial translation seem to alter the stabilization's effectiveness.

LEVEL OF EVIDENCE

IV; Cadaver study.

The Essex-Lopresti Injury:: Evaluation and Treatment Considerations

This article describes evaluation and treatment considerations for Essex-Lopresti injuries. Specific information about pattern recognition and treatment options is provided.

Digitalization of the IOM: A comprehensive cadaveric study for obtaining three-dimensional models and morphological properties of the forearm's interosseous membrane

State-of-the-art of preoperative planning for forearm orthopaedic surgeries is currently limited to simple bone procedures. The increasing interest of clinicians for more comprehensive analysis of complex pathologies often requires dynamic models, able to include the soft tissue influence into the preoperative process. Previous studies have shown that the interosseous membrane (IOM) influences forearm motion and stability, but due to the lack of morphological and biomechanical data, existing simulation models of the IOM are either too simple or clinically unreliable. This work aims to address this problematic by generating 3D morphological and tensile properties of the individual IOM structures. First, micro- and standard-CT acquisitions were performed on five fresh-frozen annotated cadaveric forearms for the generation of 3D models of the radius, ulna and each of the individual ligaments of the IOM. Afterwards, novel 3D methods were developed for the measurement of common morphological features, which were validated against established optical ex-vivo measurements. Finally, we investigated the individual tensile properties of each IOM ligament. The generated 3D morphological features can provide the basis for the future development of functional planning simulation of the forearm.

Anatomic Characteristics of the Distal Oblique Bundle of the Interosseous Membrane of the Forearm

The distal oblique bundle of the forearm is a structure that has been under vigorous investigation for the past decade. It is part of the distal interosseous membrane (DIOM) and seems to have an important stabilizing effect in the distal radioulnar joint. In this essay, we have tried to summarize the anatomical characteristics of the structure. We have also compared and contrasted this to our own experience with eight freshly frozen forearms. It is our strong belief that the distal oblique bundle (DOB) may play a keystone role in future stabilization techniques of the distal radioulnar joint, and its anatomy characteristics need to be fully investigated.

Prevalence of the distal oblique bundle of the interosseous membrane of the forearm: an anatomical study

A study was undertaken to examine the presence of the distal oblique bundle of the forearm in a large sample in order to describe its true prevalence. The study sample consisted of 200 cadaveric forearms. Fifteen were excluded due to defects in the distal interosseous membrane. In the remaining 185 specimens, the distal interosseous membrane was examined following removal of soft tissue, to determine whether a distal oblique bundle was present and whether there were connecting fibres to the distal radio-ulnar joint. The distal oblique bundle was observed in 53 specimens (29%). In 45 of these forearms (85%), one or more connecting fibres to the distal radio-ulnar joint were identified. The presence of a distal oblique bundle in 29% is less frequent than that reported in previous literature. The presence of the distal oblique bundle should be noted and may be of importance in the management of disorders of the distal radio-ulnar joint.

Magnetic resonance imaging evaluation of the distal oblique bundle in the distal interosseous membrane of the forearm

Background

Some cadaveric studies have reported the role of the distal oblique bundle (DOB) in the distal radioulnar joint stability. We aimed to determine whether the presence of the DOB can be identified and its thickness can be measured in magnetic resonance imaging (MRI) examinations.

Methods

We retrospectively reviewed 468 wrist and forearm MRIs. Inclusion criteria were wrist or forearm MRIs taken in patients older than 18 years of age, and exclusion criteria were patients with acute wrist or forearm fractures, infections, or malignant tumors. We selected 80 MRIs that provided adequate coverage of the distal interosseous membrane (DIOM). The thickness of the DIOM in the T2-weighted transverse plane was measured on the picture archiving and communicating system. We used a model-based clustering method to determine whether some individuals have thicker DIOMs that can be considered as the DOB.

Results

The thickness of the DIOM demonstrated a bimodal distribution, indicating the presence of patients with a thick DIOM (DOB). The model-based clustering method indicated that the optimal cutoff point was 1.0 mm. Twenty-six individuals (32.5%) had thick DIOMs with a mean thickness of 1.4 mm (standard deviation, 0.2 mm), while 54 individuals (67.5%) had thin DIOMs with a mean thickness of 0.6 mm (standard deviation, 0.2 mm).

Conclusion

Our study demonstrates that it is possible to identify the DOB and measure its thickness using MRI. Future in-vivo studies of the DOB using MRI in patients with distal radioulnar joint pathologies may reveal its role in the distal radioulnar joint stability.

Distal Oblique Bundle Reinforcement for Treatment of DRUJ Instability

Background Chronic, dynamic bidirectional instability in the distal radioulnar joint (DRUJ) is diagnosed clinically, based on the patient's complaints and the finding of abnormal laxity in the vicinity of the distal ulna. In cases where malunion is ruled out or treated and there are no signs of osteoarthritis, stabilization of the DRUJ may offer relief. To this end, several different techniques have been investigated over the past 90 years. Materials and Methods In this article we outline the procedure for a new technique using a tendon graft to reinforce the distal edge of the interosseous membrane. Description of Technique A percutaneous technique is used to harvest the palmaris longus tendon and to create a tunnel, just proximal to the sigmoid notch, through the ulna and radius in an oblique direction. By overdrilling the radial cortex, the knotted tendon can be pulled through the radius and ulna and the knot blocked at the second radial cortex, creating a strong connection between the radius and ulna at the site of the distal oblique bundle (DOB). The tendon is fixed in the ulna with a small interference screw in full supination, preventing subluxation of the ulna out of the sigmoid notch during rotation. Results Fourteen patients were treated with this novel technique between 2011 and October 2013. The QuickDASH score at 25 months postoperatively (range 16-38 months) showed an improvement of 32 points. Similarly, an improvement of 33 points (67-34 months) was found on the PRWHE. Only one recurrence of chronic, dynamic bidirectional instability in the DRUJ was observed. Conclusion This simple percutaneous tenodesis technique between radius and ulna at the position of the distal edge of the interosseous membrane shows promise in terms of both restoring stability and relieving complaints related to chronic subluxation in the DRUJ.