A three-dimensional quantitative analysis of carpal deformity in rheumatoid wrists

Radiographic study of the distal ulna in rheumatoid arthritis with extensor digitorum communis ruptures

OBJECTIVES

Extensor digitorum communis (EDC) rupture of the wrist often occurs in patients with rheumatoid arthritis (RA). Early operation is desirable for patients with a high risk of rupture; therefore, rheumatologists should diagnose it during daily examinations. This study aimed to clarify radiographic changes in the distal ulna and related factors associated with EDC rupture in patients with RA.

METHODS

We analysed plain radiographs of 40 patients with RA associated with EDC rupture and 62 healthy controls. We investigated the deformation of the distal ulna, Larsen grades, and radiological parameters such as ulnar variance (UV), ulnar bowing angle, dorsal protrusion (DP), and dorsal bowing angle.

RESULTS

The ratios of the ulna head deformation, Larsen grades, UV, DP, and dorsal bowing angle were significantly larger in the ruptured group than in the control group. Multiple logistic regression analysis revealed that DP and Larsen grades were significantly associated with EDC rupture.

CONCLUSIONS

Deformity of the distal ulna is evident in patients with an EDC rupture. Ulnar head deformation, high Larsen grades, and large DP are the potential risk factors for EDC rupture.

Bone resorption of the greater tuberosity after open reduction and internal fixation of complex proximal humeral fractures: fragment characteristics and intraoperative risk factors

HYPOTHESIS AND BACKGROUND

In complex proximal humeral fractures, bone resorption of the greater tuberosity is sometimes observed after open reduction and internal fixation (ORIF). However, this has not been well characterized, and risk factors for resorption are not completely understood. We aimed (1) to identify the risk factors associated with bone resorption of the greater tuberosity and (2) to quantify the geometric and bone density characteristics associated with bone resorption using 3-dimensional computed tomography models in complex proximal humeral fractures treated with ORIF.

METHODS

We identified a retrospective cohort of 136 patients who underwent ORIF of 3- or 4-part proximal humeral fractures; greater tuberosity resorption developed after ORIF in 30 of these patients. We collected demographic, fracture-related, and surgery-related characteristics and performed multivariable logistic regression analysis to identify factors independently associated with the development of greater tuberosity resorption. Furthermore, we identified 30 age- and sex-matched patients by use of propensity score matching to perform quantitative fragment-specific analysis using 3-dimensional computed tomography models. After the fragment of the greater tuberosity was identified, the number of fragments, the relative fragment volume to the humeral head, and the relative bone density to the coracoid process were calculated. Measurements were compared between matched case-control groups.

RESULTS

We found that an unreduced greater tuberosity (odds ratio [OR], 10.9; P < .001), inadequate medial support at the calcar (OR, 15.0; P < .001), and the use of an intramedullary fibular strut (OR, 4.5; P = .018) were independently associated with a higher risk of bone resorption. Quantitative fragment-specific analysis showed that greater tuberosities with a larger number of fragments (5 ± 2 vs. 3 ± 2, P = .021), smaller fragments (9.9% ± 3.8% vs. 18.6% ± 4.7%, P < .001), and fragments with a lower bone density (66.4% ± 14.3% vs. 88.0% ± 18.4%, P = .001) had higher rates of resorption.

DISCUSSION AND CONCLUSION

An unreduced greater tuberosity or inadequate medial support increases the risk of greater tuberosity resorption, as do a larger number of fracture fragments, smaller fragments, and lower bone density. Additionally, fibular strut grafting is an independent risk factor for tuberosity resorption. Further study is needed, but alternatives to strut grafting such as femoral head allograft may warrant serious consideration.

Radiotriquetral arthrodesis for rheumatoid wrist with flexor tendon rupture: A case report

Flexor tendon rupture in the wrist of patients with rheumatoid arthritis is a rare complication, and there is no standard treatment for the wrist joint. Here, we present the case of a rupture of the flexor digitorum profundus of the left index finger owing to a rheumatoid wrist. Plain radiography and computed tomography showed carpal collapse, especially lunate, and arthrosis between the capitate and lunate. For stability and mobility of the wrist and index finger, resection of the lunate and radiotriquetral (RT) arthrodesis using the distal ulna as a bone graft and arthrodesis of the distal interphalangeal joint of the index finger were performed. At 2 years postoperatively, her wrist was painless and stable on radiography without recurrence of tendon rupture, and the arc of motion of the dorsal-palmar flexion of the wrist joint was 125°. RT arthrodesis could be a surgical choice of "mobile" partial wrist arthrodesis.

Morphology and kinematics studies of the upper extremity and its clinical application in deformity correction

Morphological and kinetic studies using computer-generated bone models are helpful for determining normal articular movements and various pathological conditions of the wrist joints, forearms, and elbow joints. Previous studies consisted of kinetic analyses that were carried out by superimposing three-dimensional bone models created on a computer on the basis of CT data obtained by scanning the limbs in several different positions. We applied the techniques used in such studies and have discovered a method for carrying out surgical procedure simulations aimed at correcting upper limb deformities. In addition, we have developed a system aimed at assisting surgical procedures conducted in accordance with simulations by using patient-matched guides (patient-matched instruments, PMI) and custom-made osteosynthesis plates. Our system has allowed for accurate anatomical corrections to be carried out three-dimensionally during a simple surgical procedure. The system was clinically used in the treatment of cubitus varus as well as malunited distal radial fractures and forearm fractures. As a result, accurate correction and favorable clinical outcomes have been achieved. Together with the development of therapeutic techniques, we have also simultaneously developed the related technological system, which consists of imaging protocols aimed at reducing the amount of radiation exposure and creating statistical shape models, as well as web-based tools for communication between physicians and engineers.

Outcome of the Sauvé-Kapandji procedure for distal radioulnar joint disorder with rheumatoid arthritis or osteoarthritis: Results of one-year follow-up

OBJECTIVES

We performed the Sauvé-Kapandji procedure for treating disorders of the distal radioulnar joint (DRUJ) in patients with rheumatoid arthritis (RA) or osteoarthritis (OA). This study aimed to compare and clarify the results of the SK procedure between RA and OA patients. We report the one-year follow-up results of patients who underwent the SK procedure to correct the DRUJ disorder caused by RA or OA.

METHODS

The study included 22 wrists of 19 patients with RA and 10 wrists of nine patients with OA. Pain, grip strength and range of motion of the wrist were examined clinically. For the evaluation of the stability of the carpus, ulnar stump and bone union, parameters were measured using radiographs. Shortened disabilities of the arm, shoulder and hand questionnaire (QuickDASH) was used for functional evaluation.

RESULTS

Wrist pain reduced in all cases, and bone union was achieved in all wrists. The QuickDASH score significantly improved in both patients with RA and OA. In patients with RA, the range of motion increased significantly with regard to supination but decreased significantly with regard to palmar flexion. Carpal alignment and ulnar stump stability were maintained well at one-year follow-up.

CONCLUSION

The Sauvé-Kapandji procedure for treating disorders of the distal radioulnar joint DRUJ showed good results clinically and radiographically, irrespective of RA or OA.

In vivo 3D kinematics of the upper cervical spine during head rotation in rheumatoid arthritis

Object

The upper cervical spine is commonly involved in persons with rheumatoid arthritis (RA). Although 2D measurements have long been used in the evaluation of cervical lesions caused by RA, 2D measurements are limited in their effectiveness for detecting subtle and complex morphological and kinematic changes. The purpose of this study was to elucidate the 3D kinematics of the upper cervical spine in RA and the relationship between 3D morphological changes and decreased segmental rotational motion.

Methods

Twenty-five consecutive patients (2 men and 23 women, mean age 63.5 years, range 42–77 years) with RA (the RA group) and 10 patients (5 men and 5 women, mean age 69.9 years, range 57–82 years) with cervical spondylosis and no involvement of the upper cervical spine (the control group) underwent 3D CT of the cervical spine in 3 positions (neutral, 45° head rotation to the left, and 45° head rotation to the right). The segmental rotation angle from the occiput (Oc) to C-2 was calculated for each participant using a voxel-based registration method, and the 3D destruction of articular facets was quantified using the authors' own parameter, the articular facet index.

Results

The segmental rotation angle was significantly smaller at C1–2 and larger at Oc–C1 in the RA group compared with the control group. The degree of the destruction of the articular facet at C-1 and C-2 correlated with the segmental rotation angle.

Conclusions

In vivo 3D kinematics of the upper cervical spine during head rotation in patients with RA were accurately measured, allowing quantification of the degree of joint destruction for the first time. Joint destruction may play an important role in decreasing segmental motion of the upper cervical spine in RA.

In vivo 3-dimensional analysis of dorsal intercalated segment instability deformity secondary to scapholunate dissociation: a preliminary report

PURPOSE

To investigate in vivo 3-dimensional patterns of dorsal intercalated segment instability deformity resulting from scapholunate dissociation.

METHODS

We studied 6 patients with stage IV scapholunate dissociation in which there were complete tears of the scapholunate interosseous ligament and dorsal intercalated segment instability deformity. Of these, 3 patients had a dorsally displaced distal radius malunion, a condition known to aggravate or produce a dorsal intercalated segment instability deformity. With the wrist in neutral, we created 3-dimensional bone models of the wrists from computed tomography. We calculated centroid locations of each carpal and the rotational angle of the scaphoid and lunate relative to the radius and compared them with those of 6 normal subjects. The joint contact area was visualized to evaluate congruity of the radiocarpal and midcarpal joints.

RESULTS

In the scapholunate dissociated wrists, the scaphoid translated dorsally and radially with rotation in the direction of flexion and pronation. The lunate was extended and supinated. The capitate, trapezoid, and trapezium translated dorsally. Contact area of the radioscaphoid joint shifted dorsoradially owing to dorsoradial subluxation of the scaphoid proximal pole. Congruity was retained in the radiolunate, lunocapitate, and scaphotrapeziotrapezoid joints. In the malunion cases, the scaphoid and distal carpal rows translated more dorsally along dorsal angulation of the distal radius; therefore, incongruity of the radioscaphoid joint became more pronounced.

CONCLUSIONS

Dorsoradial subluxation of the scaphoid proximal pole over the dorsal rim of the radius led to incongruity of the radioscaphoid joint. Dorsal translation of the distal carpal row occurred with maintaining congruency of the radiolunate, lunocapitate, and scaphotrapeziotrapezoid joints. These results suggest that for realignment of the carpal axis of an advanced scapholunate dissociated wrist, we should restore scapholunate rotational malalignment and reduce the dorsally translated distal carpal row back to the anatomical position.

Spontaneous and aging-dependent development of arthritis in NADPH oxidase 2 deficiency through altered differentiation of CD11b+ and Th/Treg cells

Emerging evidence indicates that NADPH oxidase (NOX) and its reactive oxygen species (ROS) products modulate a variety of cellular events, including proliferation, differentiation, and apoptosis. In this study, we investigated the functions of NOX2 and ROS in immune modulation using NOX2 knockout (KO) mice. Interestingly, NOX2 KO mice spontaneously developed arthritis with onset at 6-7 wk of age and high incidence (60%) at 15-18 wk of age. Arthritis severity in NOX2 KO mice was proportionally increased with age and higher in females than in males. Bone destruction was confirmed by microcomputed tomography scanning and histological analyses of joints. Inflammatory factors, including TNF-α, IL-1β, and RANKL, and serum level of anti-type II collagen IgG were significantly increased in NOX2 KO mice. In addition, NOX2 deficiency perturbed the immune system upon aging. NOX2 KO mice demonstrated preferred development of CD11b+Gr-1+ myeloid cells with profound production of proinflammatory cytokines and augmented expression of IL-17 through the activation of STAT3 and RORγt in vivo. NOX2 deficiency increased differentiation of effector Th cells in vitro and decreased CD25+FoxP3+ Treg cells both in vitro and in vivo. Furthermore, adoptive transfer of NOX2-deficient CD4(+) T cells into RAG KO mice increased arthritic inflammation compared with WT cells. These results demonstrated that NOX2 deficiency affected the development of CD11b+ myeloid cells and Th17/Treg cells, and thus promoted inflammatory cytokine production and inflammatory arthritis development, strongly supporting a crucial role for ROS generation in the modulation of Th17/Treg cell development and its related inflammatory immune response upon aging.

Analysis of radiocarpal and midcarpal motion in stable and unstable rheumatoid wrists using 3-dimensional computed tomography

PURPOSE

The kinematic evaluation of carpal motion, especially midcarpal motion, in rheumatoid arthritis (RA) has been extremely difficult because of limited imaging techniques previously available. The purpose of this study was to evaluate the amount of radiocarpal and midcarpal motion in the flexion-extension plane in both stable and unstable rheumatoid wrists using three-dimensional computed tomography.

METHODS

We acquired in vivo kinematic data on 30 wrists with RA by three-dimensional computed tomography with the wrist in 3 positions: neutral, maximum flexion, and maximum extension. All cases were radiographically classified into 1 of 2 subtypes, the stable form or unstable form, according to the classification by Flury et al. We evaluated the precise range of radiocarpal and midcarpal motion using a markerless bone registration technique and calculated the individual contributions to the total amount of wrist motion in the flexion-extension plane in the different radiographic subtypes of RA.

RESULTS

The average range of motion of radiocarpal and midcarpal joint was 27 degrees +/-15 and 32 degrees +/-17, respectively. The average contribution of midcarpal motion to the total amount of wrist motion was 54%. The average contribution of midcarpal motion in the unstable form was 67%, which was significantly higher than 47% (p< .05) in the stable form.

CONCLUSIONS

Midcarpal motion of rheumatoid wrists in the flexion-extension plane was better preserved than previously thought. The contribution of midcarpal motion to the total amount of wrist motion was significantly greater (p< .05) in the unstable form than in the stable form of RA.