Carpal Instability: I. Pathoanatomy

2021 ◽  
Vol 25 (02) ◽  
pp. 191-202
Author(s):  
Rainer Schmitt ◽  
Nina Hesse ◽  
Florian Goehtz ◽  
Karl-Josef Prommersberger ◽  
Milko de Jonge ◽  
...  
Keyword(s):  
Medical History ◽  
Carpal Instability ◽  
Scapholunate Dissociation ◽  
Interosseous Ligament ◽  
Classification Feature ◽  
Profound Knowledge ◽  
Joint Surfaces ◽  
Carpal Joint ◽  
Static Instability ◽  
The Stability

AbstractThe pathoanatomy of carpal instability is multifactorial and usually complex. A thorough medical history and clinical examination are essential, as well as profound knowledge of the specific instability patterns. The stability of the wrist is ensured by the carpal joint surfaces, by intact intra-articular (particularly the scapholunate interosseous ligament) and intracapsular ligaments, and by crossing extensor and flexor tendons, the latter making the proximal carpal row an “intercalated segment.” An important classification feature is the distinction between dissociative and nondissociative forms of carpal instability. Among others, scapholunate dissociation, lunotriquetral dissociation, midcarpal instability, and ulnar translocation are the most common entities. Early forms of instability are considered dynamic. In the natural course, static instability of the wrist and osteoarthritis will develop. This review focuses on the pathoanatomical fundamentals of the various forms of carpal instability.

On the Design of Contact Member Surface Shape of Bolted Joints to Minimize Clamping Load Loss

2018 ◽  
Author(s):  
Linbo Zhu ◽  
Yifei Hou ◽  
Abdel-Hakim Bouzid ◽  
Jun Hong
Keyword(s):  
Contact Surface ◽  
High Performance ◽  
Thermal Loading ◽  
Structural Integrity ◽  
Bolted Joints ◽  
Surface Shape ◽  
Geometrical Shape ◽  
Joint Surfaces ◽  
Joint Contact ◽  
The Stability

Metal to metal contact between joint surfaces is widely used in bolted joints to obtain a rigid and a high performance connection. However, a significant amount of clamping load is lost when the joint is subjected to mechanical and thermal loading including creep and fatigue. In practice, to prevent bolt loosening, additional parts such as spring washers, double nut, spring lock washers, Nyloc nut and so on are used. Those methods are costly and influence the stability of the joint and affect its structural integrity. It is well established that a small compression displacement in clamping parts leads to a big clamping load loss in stiff joints. This paper discusses the relationship between connection stiffness and clamping load and presents a method that improves clamping load retention during operation by a careful design of the member contact surface shape. A single bolted joint with two clamping parts is modeled using finite element method (FEM). A method is proposed to obtain a specific stiffness by an optimized geometrical shape of the joint contact surfaces. The result shows that the contact surface shape based on a gradually varying gap can improve the retention of the initial clamping load. Furthermore, a formula of the connection stiffness based on the curve fitting technique is proposed to predict residual clamping load under different external load and loosening.

Comparison of Normal Capitate Mid-Carpal Joint Mechanics With the Effects of Scapholunate Dissociation Injury

2011 ◽  
Author(s):  
Madhan Sai Kallem ◽  
Sang-Pil Lee ◽  
Terence E. McIff ◽  
E. Bruce Toby ◽  
Kenneth J. Fischer
Keyword(s):  
Contact Mechanics ◽  
Surgical Techniques ◽  
Ligament Injury ◽  
Joint Mechanics ◽  
Scapholunate Dissociation ◽  
Carpal Collapse ◽  
Contact Patterns ◽  
Carpal Joint ◽  
Slac Wrist

The wrist is one of the most complicated multibody joints in the human body. It can be subject to many injuries. Scapholunate (SL) dissociation is a relatively common injury that is particularly difficult to diagnose and treat. Without treatment, SL dissociation is known to progress to scapholunate advance collapse (SLAC wrist) and associated osteoarthritis (OA) [1]. Traumatic arthropathy of the wrist due to scapholunate dissociation has a definitive pattern from onset to severe bone and joint degeneration. The altered radiocarpal and SL mechanics with SL dissociation may be accompanied by a secondary carpal collapse between the capitate and lunate [2]. The initial SL disruption causes apparent changes in joint kinematics and contact patterns. Thus, understanding normal and abnormal in vivo contact mechanics as a result of SL ligament injury may lead to more effective treatments that may even prevent the onset of OA. In addition, in vivo contact mechanics data after surgical treatment may help determine the effectiveness of various surgical techniques which are used to correct SL injury.

Volar Intercalated Segment Instability as a Result of Spontaneous Rupture of The Supporting Ligaments of the Wrist Due to Longterm Systemic Steroid Medication.

1985 ◽  
Vol 10 (3) ◽  
pp. 395-398
Author(s):  
M. J. BELL ◽  
R. Y. McMURTRY
Keyword(s):  
Systemic Steroid ◽  
Scapholunate Dissociation ◽  
Interosseous Ligament ◽  
Scaphoid Fractures ◽  
Traumatic Origin ◽  
Post Traumatic ◽  
Ligament Laxity ◽  
The One ◽  
Dorsal Intercalated Segment Instability ◽  
Ligament Disruption

Linscheid and Dobyns (1972), in a classical article on post-traumatic instability of the wrist described two major types of instability, dorsal and volar. The dorsal intercalated segment instability (D.I.S.I.) was the more common and occurred with scapholunate dissociation and displaced scaphoid fractures. The instability occurred in these conditions as a result of the scaphoid losing its ability to support the carpus. They presented five cases of volar intercalated segment instability (V.I.S.I.) of which four were related to congenital ligament laxity and not to traumatic ligament disruption. In the one case of traumatic origin they felt that the capitolunate ligament was ruptured. However, more recent publications by Taleisnik, Prietto (1982) and Reagan, (1984) have proposed that for V.I.S.I. to occur the lunate triquetral interosseous ligament must be disrupted. We report this case as it demonstrates which ligamentous structures are torn for V.I.S.I. to occur. In addition, these ligament disruptions were pathological and occurred spontaneously as a result of longterm systemic steroid medication.

Radiological evaluation of scapholunate intercarpal ligamentoplasty for chronic scapholunate dissociation in cadavers

2017 ◽  
Vol 43 (4) ◽  
pp. 387-393 ◽  
Author(s):  
Lionel Athlani ◽  
Nicolas Pauchard ◽  
Gilles Dautel
Keyword(s):  
Normal Values ◽  
Cadaveric Study ◽  
Radiological Evaluation ◽  
Joint Stability ◽  
Scapholunate Dissociation ◽  
Interosseous Ligament ◽  
Segmental Instability ◽  
Treatment Groups ◽  
Scapholunate Instability ◽  
Significant Difference

We performed a cadaveric study to evaluate radiological performance of a technique for scapholunate intercarpal ligamentoplasty designed for treating reducible scapholunate dissociation. We created scapholunate instability in 12 fresh adult cadaveric forearms by sectioning the dorsal scapholunate interosseous ligament and the dorsal intercarpal ligament. All wrists showed scapholunate diastasis, dorsal intercalated segmental instability and posterior scaphoid subluxation. We performed scapholunate intercarpal ligamentoplasty in six wrists and Garcia-Elias three-ligament tenodesis in another six. Wrists were examined radiographically both after ligament sectioning and after ligamentoplasty to compare static and dynamic scapholunate gaps and scapholunate and capitolunate angles. Improvement was statistically significant in all measurements, reflecting a return to normal values. Posterior scaphoid subluxation was also corrected. There was no significant difference between the two treatment groups. Our findings suggest that ligamentoplasty can restore scapholunate joint stability and normal carpal anatomy.

Scaphoid and Capitate Fracture with Concurrent Scapholunate Dissociation

2006 ◽  
Vol 31 (1) ◽  
pp. 76-78 ◽  
Author(s):  
M. OSTI ◽  
R. ZINNECKER ◽  
K. P. BENEDETTO
Keyword(s):  
Operative Treatment ◽  
Functional Result ◽  
Carpal Instability ◽  
Scapholunate Dissociation ◽  
Rare Lesion ◽  
Capitate Fracture ◽  
Unusual Injury

Combined fracture of the scaphoid and capitate bones with concurrent scapholunate dissociation, but without severe dislocation, is a rare lesion which results in significant carpal instability and requires operative treatment. We report a case of this unusual injury and its functional result after 20 months.

scholarly journals Acute Arthroscopic Removal of a Bullet Embedded in the Glenoid: A Case Report

2021 ◽  
Vol 11 (3) ◽  
Author(s):  
Jonathan Guevara ◽  
Karthikeyan Chinnakkannu ◽  
Sivashanmugam Raju
Keyword(s):  
Case Report ◽  
Bone Defect ◽  
Shoulder Arthroscopy ◽  
Left Shoulder ◽  
Lumbar Level ◽  
Joint Surfaces ◽  
Arthroscopic Removal ◽  
Cord Injury ◽  
The Stability ◽  
Vein Injury

Introduction: Retained bullets in joint spaces have been shown to cause both mechanical and chemical damage to the joint surfaces, leading to the risk of arthritis if untreated. Case Report: A case of arthroscopic treatment for a gunshot to the shoulder with a retained bullet embedded in the glenoid is presented. The patient presented with multiple gunshots to his back and extremities, including gunshot to the left leg with popliteal vein injury, gunshot to the back with lumbar level laminar fractures and acute spinal cord injury, and gunshot to the left shoulder with a retained bullet in the posterior superior glenoid. Conclusion: Shoulder arthroscopy can be successfully employed to retrieve larger embedded bullet or foreign body with the help of tools such as laparoscopic graspers. Even with significant glenoid bone defect, the stability of the shoulder joint does not get compromised if the bone defects are located posterosuperiorly. Keywords: Retained bullet, shoulder arthroscopy, gunshot, glenoid bone defect, humeral head fracture.

Proptosis of the eye: a potential form of Madelung’s disease

2021 ◽  
Vol 14 (9) ◽  
pp. e243669
Author(s):  
Shayan Soomro ◽  
Kimia Ziahosseini ◽  
Poonam Sharma
Keyword(s):  
Adipose Tissue ◽  
Case Report ◽  
Optic Nerve ◽  
Medical History ◽  
Madelung's Disease ◽  
Madelung’S Disease ◽  
Potential Form ◽  
History Of ◽  
The Stability ◽  
Genetic Form

Madelung’s disease is a rare disorder characterised by excessive and symmetrical deposits of adipose tissue, typically in the cervicofacial region. Alcohol is a known cause of the condition, however, there are reports that this condition is genetically inherited. Lipomatosis of the orbit has been described in the alcoholic Madelung’s disease, however, in our case report, we believe this is the first reported instance of proptosis caused by the genetic form of the condition. We present a 69-year-old woman, with a medical history of genetic Madelung’s disease, who presented with bilateral proptosis worse in her right eye. Her ocular examination was normal apart from exophthalmometry, showing bilateral proptosis. This was confirmed by an MRI, which further showed intraorbital fat deposition bilaterally. Due to the stability of her condition, no treatment was deemed necessary. We highlight the importance of monitoring for progressive optic nerve compromise and liposarcomatous malignant transformation.

Global Static Instability of Risers

1984 ◽  
Vol 28 (04) ◽  
pp. 261-271
Author(s):  
Michael M. Bernitsas ◽  
Theodore Kokkinis
Keyword(s):  
Boundary Conditions ◽  
Internal Pressure ◽  
Stability Boundary ◽  
Critical Length ◽  
Bending Rigidity ◽  
Buckling Mode ◽  
Stability Boundaries ◽  
Various Boundary Conditions ◽  
Static Instability ◽  
The Stability

Global instability of risers depends on riser weight, internal and external fluid static pressure forces, tension exerted at the top of the riser, and boundary conditions. The purpose of this work is to study the effects of these factors on the stability boundaries of risers and specifically.(i) compare buckling loads for various boundary conditions; (ii) find the long-riser instability behavior from the asymptotics of the stability boundaries; (iii) find the short-riser instability behavior; (iv) analyze the relative effects of boundary conditions, weight, internal pressure, and bending rigidity on stability; (v) show the variation of the stability boundary shape with the order of the buckling mode; and (vi) compare the critical length at which risers in tension over their entire length may buckle due to internal pressure, for various boundary conditions.

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