The influence of cartilage thickness at the sigmoid notch on inclination at the distal radioulnar joint

Magnetic Resonance Imaging Assessment of Ulnar Wrist Pain: A Practical Guide for Surgeons

Ulnar-sided wrist pain is a challenging clinical scenario due to multiple overlapping pathologies and involved anatomic structures. Advanced imaging such as magnetic resonance imaging can be used as an effective diagnostic adjunct if interpreted correctly. In this article, clinically relevant structures and radiographic correlates of the ulnar wrist are discussed and a corresponding systematic approach to reviewing magnetic resonance imaging is presented.

A modified partial wedge-shaped metaphyseal ulnar osteotomy for the treatment of ulnar impaction syndrome with reverse oblique sigmoid notch

We describe a modified metaphyseal ulnar osteotomy to treat ulnar impaction syndrome with a reverse oblique sigmoid notch. Based on a computational analysis of radiographs, a modified wedge metaphyseal ulnar osteotomy was devised with its apex positioned at the ulnar styloid base to avoid impaction between the sigmoid notch and ulnar head. Subsequently, nine patients with ulnar impaction syndrome and a reverse oblique sigmoid notch underwent this operation, combined with arthroscopic exploration and transosseous triangular fibrocartilage complex repair. The mean follow-up was 14 months. All patients achieved bone union within 5 weeks, with no degenerative changes being observed during the follow-up assessments. The final follow-up assessments revealed decreases in ulnar variance and in the scores for Visual Analogue Scale, Quick Disabilities of the Arm, Shoulder and Hand questionnaire and the Patient-Rated Wrist Evaluation. All patients achieved excellent or good grades on the Modified Mayo Wrist Score. This technique is effective in treating the ulnar impaction syndrome with a reverse oblique sigmoid notch.Level of evidence: IV.

Anatomic and Biomechanical Study of the Forearm Interosseous Membrane, Distal Oblique Bundle, and Triangular Fibrocartilage Complex: Role in Galeazzi Fracture Dislocation

Purpose

The purpose of this study was to measure distal radioulnar joint (DRUJ) dislocation and radioulnar displacement associated with sequential sectioning of the different bands of the interosseous membrane and triangular fibrocartilage complex in the simulation of a Galeazzi fracture dislocation.

Methods

Twelve fresh-frozen cadaver forearms were dissected. We examined the anatomy and function of the forearm interosseous membrane. Each forearm was then mounted onto a biomechanical wrist and forearm device. In the control group, radial osteotomy was performed and the degree of DRUJ displacement with progressive loads was measured. In addition to radial osteotomy, in group 1, the central band (CB) was sectioned; in group 2, the CB, distal membranous portion of the interosseous membrane, and distal oblique bundle were sectioned; and in group 3, the CB, distal membranous portion of the interosseous membrane, distal oblique bundle, and triangular fibrocartilage complex were sectioned.

Results

The radioulnar displacement (mm) at 25 N, 50 N, and 75 N was recorded. In group 1, applying progressive loads resulted in an average DRUJ displacement of 4.3, 5.9, and 7.9 mm, respectively. In group 2, the displacement was 5.2, 5.7, and 6.9 mm, respectively. In group 3, the displacement was 6.2, 8.1, and 9.9 mm, respectively. Our study showed a correlation between increase in the load applied to the same injury and the degree of displacement (P = .001). In group 3, the degree of DRUJ displacement was statistically increased compared to the other groups (P = .04).

Conclusions

Migration of the radius under loads implies disruption of both the CB and triangular fibrocartilage complex. The distal oblique bundle by itself does not seem to have a relevant role in radioulnar displacement at the DRUJ.

Clinical relevance

This study provides insights into the interosseous membrane and stability of the DRUJ, which can contribute to a better understanding of Galeazzi fracture-dislocations.

Midsectional Magnetic Resonance Imaging Analysis of the Sigmoid Notch of the Distal Radioulnar Joint

Purpose  This study describes the anatomy and analyzes the variations of the midsectional morphology of the sigmoid notch. Methods  The wrists of 50 patients with suspected scaphoid fracture were evaluated by magnetic resonance imaging (MRI). Sigmoid notch length, volar and dorsal rim heights, insertion length of the volar radioulnar ligament, and Tolat morphology classification were measured on T1-weighted axial plane MRI. Ulnar variance and distal radioulnar joint (DRUJ) inclination were assessed on anteroposterior radiographs. Results  The most common sigmoid notch shapes were types C (C-shaped, 60%) and B (ski-slope, 30%), followed by types D (S-shaped, 6%) and A (flat, 4%). Types A and B had a flat dorsal rim (mean 0.77 ± 1.09 mm, range 0.0-1.54 mm, and mean 0.22 ± 0.3 mm, range 0.0-0.76 mm, respectively). Types C and D had more prominent dorsal rims (means 1.47 ± 0.59 mm, range 0.66-2.57 mm, and mean 1.6 ± 0.97 mm, range 0.8-2.68 mm, respectively). The average volar lip length was 1.60 ± 1.11 mm (range, 0.0-4.10). The dorsovolar length of the radius was 18.4 ± 2.01 mm; the length of the sigmoid notch was 14.3 ± 1.73 mm. The type of sigmoid notch according to Tolat was significantly associated with volar lip length ( p  = 0.005). The type of sigmoid notch was not associated with ulnar variance or DRUJ inclination. The length of the sigmoid notch was significantly associated with the type of sigmoid notch ( p  = 0.005). The analysis demonstrated a negative association between the sigmoid notch length and the volar insertion of the radioulnar ligament ( p  = 0.019). Conclusions  The transversal morphology of the sigmoid notch was either flat with the least congruence (similar to type A of Tolat), with volar congruence only (similar to type B), or with volar and dorsal congruence (similar to types C and D). A shorter sigmoid notch may be compensated by a broader insertion of the volar radioulnar ligament. Clinical Relevance  The measurements and correlations demonstrated in this study can be a guide when considering reconstructive procedures or dealing with the instability of the DRUJ.

Radiographic changes in the distal ulna in non-rheumatoid patients with extensor digitorum communis ruptures

INTRODUCTION

Osteoarthritis of the distal radioulnar joint (DRUJ) is relatively common in elderly people. Extensor digitorum communis (EDC) ruptures occasionally and occurs with or without prior signs in these people. The purpose of this study was to clarify the radiographic changes in the distal ulna associated with EDC rupture.

MATERIALS AND METHODS

We analyzed plain radiographs of 71 patients with non-rheumatoid arthritis and 40 controls. Radiographic changes in the distal ulna were categorized into normal, osteoarthritic-change (OA-change), and taper. We measured the ulnar variance (UV) and ulnar bowing angle in the posteroanterior radiographs and the dorsal bowing angle (DBA) and dorsal protrusion (DP) in the lateral radiographs. The shape of the sigmoid notch (SN) was categorized into flat, radial inclination, and dimple. The primary outcome was a comparison of radiographic parameters between the patient and the control groups. The secondary outcome was an analysis of the type of SN to investigate factors affecting ulnar deformation.

RESULTS

The ratio of the radiographic change in the ulna, UV, DBA, and DP was significantly larger in the patient group than in the control group. Patients with the radial inclination type of SN showed a greater UV than those with the dimple type.

CONCLUSIONS

Deformation of the distal ulna, a large UV, dorsal penetration, and dorsal bowing was related to EDC rupture. Regarding the large UV, the lunate shaved the upper half of the distal ulna, whereas the DRUJ shaved the lower half. These processes formed a tapered ulna head. A large UV and an inclination of the DRUJ played a role in ulnar head deformation.

Morphologic Characteristics of the Sigmoid Notch of the Distal Radius for Patients With Peripheral Triangular Fibrocartilage Complex Tear

The distal radioulnar joint (DRUJ) is stabilized by the bony anatomy of the contact surfaces. The authors analyzed the morphologic characteristics and radiologic parameters at the sigmoid notch of patients with a peripheral triangular fibrocartilage complex (TFCC) tear compared with asymptomatic patients. Preoperative axial computed tomography scans were reviewed for 76 wrists with peripheral TFCC injuries, including foveal avulsion, and 76 wrists of age- and sex-matched control subjects. The authors used axial computed tomography scans of the DRUJ to classify the patients into 4 groups according to the type of sigmoid notch, namely, flat face, ski-slope, C-type, and S-type. They also measured the tilting angle, depth, width of the sigmoid notch, and radioulnar ratio (RUR). Statistical analyses were performed with the chi-square test or paired t test (P<.05). The mean proportions of flat face, ski-slope, C-type, and S-type sigmoid notches among patients with peripheral TFCC injuries were 42%, 22%, 29%, and 7%, respectively, whereas those for the control group were 33%, 1%, 65%, and 1%, respectively (P<.05). The tilting angle was lower (TFCC injury, 84.5°; control, 86.2°; P<.05) and the RUR was significantly higher (TFCC injury, 0.67; control, 0.56) in the TFCC group, particularly for men (P<.05). Depth (TFCC injury, 1.0 mm; control, 1.3 mm; P>.05) and width (TFCC injury, 14.8 mm; control, 14.5 mm; P>.05) were similar between the groups. Patients with ski-slope or dorsally tilted sigmoid notches may be at greater risk for peripheral TFCC injuries. [Orthopedics. 2021;44(6):e729-e734.].

Supercritical carbon dioxide decellularized porcine cartilage graft with PRP attenuated OA progression and regenerated articular cartilage in ACLT-induced OA rats

Knee osteoarthritis (OA) is a common degenerative articular disorder and considered one of the primary causes of pain and functional disability. Knee OA is prevalent in 10% of men and 13% of women aged 60 years above. The study aims to use cartilage tissue engineering that combines the triads of decellularized porcine cartilage graft as "scaffold," plasma rich platelet (PRP) as "signal" and chondrocytes from rat as "cell" to attenuate ACLT-induced OA progression and regenerate the knee cartilage in rats. Decellularization of the porcine cartilage was characterized by hematoxylin and eosin, 4,6-Diamidino-2-phenylindole staining, scanning electron microscopy and residual DNA quantification. The protective effect of decellularized porcine cartilage graft (dPCG) was evaluated by intra-articular administration in surgically induced anterior cruciate ligament transection (ACLT) rat osteoarthritis (OA) model. Supercritical carbon dioxide technology completely decellularized the porcine cartilage. Intra-articular administration of dPCG with or without PRP significantly reduced the ACLT-induced OA symptoms and attenuated the OA progression. Pain-relief by dPCG with or without PRP was assessed by capacitance meter and improved articular cartilage damage in the rat knee was characterized by X-ray and micro-CT. Besides, the histological analysis depicted cartilage protection by dPCG with or without PRP. The repairation and attenuation effect by dPCG with or without PRP in the articular knee cartilage damage were also explored by safranin-O, type II collagen, aggrecan and SOX-9 immuno-staining. To conclude, intra-articular administration of dPCG with or without PRP is efficient in repairing the damaged cartilage in the experimental OA model.

Long-term radiographic outcomes and functional evaluation of ulnar shortening osteotomy in patients with ulnar impaction syndrome and reverse oblique sigmoid notch: a retrospective case series study

BACKGROUND

Ulnar shortening osteotomy (USO) is an effective treatment for ulnar impaction syndrome. However, there have been reports of osteoarthritis (OA) at the distal radioulnar joint (DRUJ) when USO was performed on patients with a reverse oblique sigmoid notch. This study aimed to evaluate the radiographic and functional outcomes following USO in patients with a reverse oblique sigmoid notch.

METHODS

We retrospectively reviewed patients having a reverse oblique sigmoid notch who underwent USO for ulnar impaction syndrome between 2002 and 2013. We evaluated radiographic changes of the DRUJ and functional outcomes of patients.

RESULTS

We enrolled 22 patients (22 wrists) with an average age of 49.6 years and a mean follow-up of 93.2 (range, 36-179; standard deviation [SD], 38.2) months. We found that there were changes in the inclination angle of the sigmoid notch, from an average reverse oblique of 14.9^o (range, 11^o-23^o; SD, 3.4^o) preoperatively to a more parallel 5.1^o (range, 0^o-11^o; SD, 3.2^o) at the final follow-up. The functional results at the final follow-up were good, with a mean visual analogue scale for pain of 0.2 (range, 0-1; SD, 0.4) at rest and 1.3 (range, 0-3; SD, 0.9) during activity, QuickDASH of 15.1 (range, 2.3-34.1; SD, 8.8), and modified Mayo Wrist Score of 91.6 (range, 70-100; SD, 6.4). Seven wrists (31.8%) had changes compatible with OA, but the wrists did not exhibit a significantly worse function when compared to wrists without OA changes, except for supination motion and grip strength.

CONCLUSIONS

For patients with a reverse oblique sigmoid inclination following USO, we observed that the inclination angle had a tendency to become parallel and some patients developed OA at the DRUJ. However, long-term functional outcomes could still be good. The reverse oblique sigmoid inclination does not seem to be an absolute contraindication for USO.

Morphology at the Distal Radioulnar Joint: Identifying the Prevalence of Reverse Obliquity

Background  Recent advances in the understanding of ulnar-sided wrist pathologies such as ulnar abutment syndrome (UAS) have brought increased attention to the anatomy of the distal radioulnar joint (DRUJ). Previous work established three anatomical variants of the sigmoid notch (parallel, oblique, and reverse oblique). The reverse oblique DRUJ poses theoretical risk of increased contact forces following ulnar shortening osteotomy, a common method of treating UAS. Purpose  As prevalence of reverse oblique morphology has been under-reported, this study aims to better define the prevalence of reverse oblique morphology in the adult population. Methods  Institutional Review Board-approved review of 1,000 radiographs over a 2-year period was performed. Demographic data and radiographic measurements were recorded (ulnar variance, notch inclination, and presence of arthritis). Correlation tests, a test of proportions, a t -test, and linear and logic regression tests were used to examine associations between ulnar variance, sigmoid inclination, sex, age, and presence of arthritis. Results  One thousand radiographs were analyzed revealing prevalence rates of: parallel-68%, oblique-26%, and reverse oblique-6%. Females were significantly more likely to have reverse inclination. No significant correlation was noted for morphology by age. Ulna positive variance was negatively correlated with reverse inclination. DRUJ arthritis was noted in 14% of patients. Higher sigmoid inclination was associated with higher odds of presence of arthritis, adjusting for sex and age. Higher incidence of arthritis was noted among patients with the oblique (20.8%) or reverse oblique (24.6%) compared with parallel (10.5%) morphology. Conclusion  This series of 1,000 radiographs demonstrates a 6% overall prevalence of reverse obliquity. This large dataset allows for better quantification of the prevalence of DRUJ morphologies and determination of correlations that have clinical implications for patients with ulnar-sided wrist pathology. Level of Evidence  This is a Level IV study.

The correlation between shape of the sigmoid notch of the distal radius and the risk of triangular fibrocartilage complex foveal tear

Aims

The aim of this study was to analyze the association between the shape of the distal radius sigmoid notch and triangular fibrocartilage complex (TFCC) foveal tear.

Methods

Between 2013 and 2018, patients were retrospectively recruited in two different groups. The patient group comprised individuals who underwent arthroscopic transosseous TFCC foveal repair for foveal tear of the wrist. The control group comprised individuals presenting with various diseases around wrist not affecting the TFCC. The study recruited 176 patients (58 patients, 118 controls). The sigmoid notch shape was classified into four types (flat-face, C-, S-, and ski-slope types) and three radiological parameters related to the sigmoid notch (namely, the radius curvature, depth, and version angle) were measured. The association of radiological parameters and sigmoid notch types with the TFCC foveal tear was investigated in univariate and multivariate analyses. Receiver operating characteristic curves were used to estimate a cut-off for any statistically significant variables.

Results

Univariate analysis showed that the flat-face type was more prevalent in the patients than in the control group (43% vs 21%; p = 0.002), while the C-type was lower in the patients than in the control group (3% vs 17%; p = 0.011). The depth and version angle of sigmoid notch showed a negative association with the TFCC foveal tear in the multivariate analysis (depth: odds ratio (OR) 0.380; p = 0.037; version angle: OR 0.896; p = 0.033). Estimated cut-off values were 1.34 mm for the depth (area under the curve (AUC) = 0.725) and 10.45° for the version angle (AUC = 0.726).

Conclusion

The proportion of flat-face sigmoid notch type was greater in the patient group than in the control group. The depth and version angle of sigmoid notch were negatively associated with TFCC foveal injury. Cite this article: Bone Joint J 2020;102-B(6):749–754.

A three-dimensional virtual morphometry study of the sigmoid notch of the distal radius

PURPOSE

Our primary objectives were to create a reliable, noninvasive method for three-dimensional morphometry of deep bony parameters within the sigmoid notch of the distal radius, to identify its morphological patterns, and to identify any significant variation between the left and the right wrists. Our secondary objectives were to obtain morphometric values that could represent our population and to identify any possible ethnic variations.

METHODS

Computed tomography scans of 102 wrists from 51 healthy individuals were analyzed using a virtualization software. Four anatomical parameters at the distal radius sigmoid notch, namely, the radius of curvature, depth, version angle, and sagittal slope were measured. Morphological patterns of the sigmoid notch surface were identified. The results were statistically analyzed to assess the reliability of the technique and were compared with previously published literature.

RESULTS

Comparing our findings with previously published values, our study revealed a slightly larger radius of curvature and sagittal slope, while revealing a smaller depth and version. We identified the S-type, C-type, and ski-slope morphological variants. The flat-face morphological variant, however, was not identified. The sigmoid notch at the left and right wrists were similar, except for the radius of curvature.

CONCLUSION

This study demonstrates a noninvasive, fast, reliable, and reproducible technique for analyzing the sigmoid notch of the distal radius. In wrist injuries with intact distal radius sigmoid notch but involving comminuted fractures of the ulnar head, ulnar head replacement may be indicated. In such cases, analysis of the ipsilateral intact sigmoid notch would allow us to prepare an ulnar head prosthesis of appropriate size.

Morphological characteristics of the sigmoid notch of the distal radius affect the stress distribution patterns in the distal radioulnar joint

The aim of this study was to clarify the effects of morphological patterns of the sigmoid notch on the stress distribution across the articular surface of the distal radioulnar joint using a computed tomography osteoabsorptiometry method. Fourteen wrists from 13 patients were classified into two groups according to the type of sigmoid notch, namely the 'C' type and ski-slope sigmoids, and the percentages of high-density areas on the articular surface were quantitatively analysed. The percentage of the high-density area of the dorsal region in the ski-slope sigmoid group was significantly greater than that of the 'C' type sigmoid group (16% vs 4.1%) and of the volar region of the ski-slope sigmoid group (16% vs 2.4%). The results indicate that bony morphological differences in the radial sigmoid notch affect the stress distribution pattern through the distal radioulnar joint.

Comparison of pain behaviour and osteoarthritis progression between anterior cruciate ligament transection and osteochondral injury in rat models

Objectives

In this study, we compared the pain behaviour and osteoarthritis (OA) progression between anterior cruciate ligament transection (ACLT) and osteochondral injury in surgically-induced OA rat models.

Methods

OA was induced in the knee joints of male Wistar rats using transection of the ACL or induction of osteochondral injury. Changes in the percentage of high limb weight distribution (%HLWD) on the operated hind limb were used to determine the pain behaviour in these models. The development of OA was assessed and compared using a histological evaluation based on the Osteoarthritis Research Society International (OARSI) cartilage OA histopathology score.

Results

Both models showed an increase in joint pain as indicated by a significant (p < 0.05) decrease in the values of %HLWD at one week post-surgery. In the osteochondral injury model, the %HLWD returned to normal within three weeks, while in the ACLT model, a significant decrease in the %HLWD was persistent over an eight-week period. In addition, OA progression was more advanced in the ACLT model than in the osteochondral injury model. Furthermore, the ACLT model exhibited a higher mean OA score than that of the osteochondral injury model at 12 weeks.

Conclusion

The development of pain patterns in the ACLT and osteochondral injury models is different in that the OA progression was significant in the ACLT model. Although both can be used as models for a post-traumatic injury of the knee, the selection of appropriate models for OA in preclinical studies should be specified and relevant to the clinical scenario.

Cite this article: T. Tawonsawatruk, O. Sriwatananukulkit, W. Himakhun, W. Hemstapat. Comparison of pain behaviour and osteoarthritis progression between anterior cruciate ligament transection and osteochondral injury in rat models. Bone Joint Res 2018;7:244–251. DOI: 10.1302/2046-3758.73.BJR-2017-0121.R2.