Dupuytren's contracture-associated SNPs increase SFRP4 expression in non-immune cells including fibroblasts to enhance inflammation development.

Dupuytren's contracture (DC) is an inflammatory fibrosis characterized by fibroproliferative disorders of the palmar aponeurosis, for which there is no effective treatment. Although several genome-wide association studies have identified risk alleles associated with DC, the functional linkage between these alleles and the pathogenesis remains elusive. We here focused on two single nucleotide polymorphisms (SNPs) associated with DC, rs16879765 and rs17171229, in secreted frizzled related protein 4 (SFRP4). We investigated the association of SRFP4 with the IL-6 amplifier, which amplifies the production of IL-6, growth factors and chemokines in non-immune cells and aggravates inflammatory diseases via NF-κB enhancement. Knockdown of SFRP4 suppressed activation of the IL-6 amplifier in vitro and in vivo, whereas the overexpression of SFRP4 induced the activation of NF-κB-mediated transcription activity. Mechanistically, SFRP4 induced NF-κB activation by directly binding to molecules of the ubiquitination SFC complex, such as IkBα and ßTrCP, followed by IkBα degradation. Furthermore, SFRP4 expression was significantly increased in fibroblasts derived from DC patients bearing the risk alleles. Consistently, fibroblasts with the risk alleles enhanced activation of the IL-6 amplifier. These findings indicate that the IL-6 amplifier is involved in the pathogenesis of DC, particularly in patients harboring the SFRP4 risk alleles. Therefore, SFRP4 is a potential therapeutic target for various inflammatory diseases and disorders, including DC.

The sole rupture of flexor digitorum tendons to the index finger following volar locking plate fixation of distal radius fracture: A case report.

Distal radius fracture is a common injury, especially in elderly people, and internal fixation with volar locking plate (VLP) is becoming an increasingly popular technique for the management of displaced and/or unstable distal radius fractures. One of the most common complications of this treatment is the flexor tendon rupture, mostly of the flexor pollicis longus (FPL). While the rupture of flexor digitorum tendons to the index (FDI) mostly occurs concomitantly with the rupture of FPL after the treatment using volar plating for distal radial fracture, sole rupture of the FDI without FPL rupture is very rare. Here, we report a case of the sole rupture of FDI after volar locking plating and analyze its pathogenesis indicating that the lift-up of the distal ulnar edge of the plate related to the malcorrection of the fracture site is the culprit for this specific complication.

Glenoid stress distribution in baseball players using computed tomography osteoabsorptiometry: a pilot study.

BACKGROUND: It is important to understand the loading conditions when considering the pathology of shoulder disorders in overhead athletes. However, because throwing is a complicated motion and methods to directly determine stress distribution are complex, direct measurement of the stress distribution across the glenohumeral joint has not been attempted. Subchondral bone density reportedly reflects the cumulative stress acting on a joint surface under actual loading conditions. QUESTIONS/PURPOSES: To assess alterations in stress distribution across the glenoid cavity caused by pitching, we investigated the distribution of subchondral bone density in nonathletic volunteers and asymptomatic baseball players, including fielders and pitchers. METHODS: We collected CT imaging data from the dominant-side shoulder of 10 nonathletic volunteers (controls), 10 fielders, and 10 pitchers in a competitive college baseball league (all men aged 19­24 years, mean 20.7 years). We measured the distribution of subchondral bone density of the glenoid cavity using CT osteoabsorptiometry. The obtained stress distribution map was divided into four segments: anterosuperior, anteroinferior, posteroinferior, and posterosuperior regions. We quantitatively analyzed the location and percentages of high-density regions on the articular surface. RESULTS: The percentages of high-density regions, including the anteroinferior and posterior segments, were greater in pitchers and fielders than in controls. The percentages of high-density regions did not differ between pitchers and fielders. CONCLUSIONS: The bicentric density patterns indicated that the cumulative force of pitching activity affected the long-term stress distribution across the glenoid cavity. CLINICAL RELEVANCE: Our data should be useful for analyzing pitching activity and clarifying the pathology of shoulder disorders associated with throwing.

Prevention of instability of the proximal end of the radius after radial head resection using an anconeus muscle flap.

Resection of the radial head frequently causes instability of the proximal end of the radius. To prevent this instability, we performed a stabilization technique using an anconeus muscle flap. Since 2003, six patients with radiocapitellar joint dysfunction have been treated with radial head resection combined with stabilizing its proximal end using an anconeus muscle flap. At a mean follow-up of 51 months, all patients were free from elbow pain and the mean Mayo Elbow Performance Score and the Disabilities of the Arm, Shoulder and Hand score significantly improved. Radiographic findings showed no apparent instability of the proximal radius. The anconeus is useful as a reliable muscle flap for preventing instability of the proximal radius after a radial head resection. This procedure does not require any microvascular techniques and makes it possible to apply a pedicled muscle flap using a relatively simple technique without any considerable risks of elbow dysfunction.

Distribution of bone mineral density at osteochondral donor sites in the patellofemoral joint among baseball players and controls.

BACKGROUND: To theoretically minimize complications of osteochondral graft harvest from the knee, grafts should be obtained from the site of lowest stress distribution across the joint. HYPOTHESIS: Long-term stress distribution over the patellofemoral (PF) joint surface is not equal in athletes. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Measurement of subchondral bone density can determine long-term resultant stress acting on an articular surface in living joints. Our analysis was performed using computed tomography (CT) image data obtained from bilateral knees of 10 college baseball fielders (fielder group) and 10 college baseball pitchers (pitcher group) and 2 control groups, including 10 college soccer players (soccer group) and 10 nonathletes (nonathlete group). The distribution pattern of subchondral bone density throughout the articular surface of the PF joint was assessed using the CT osteoabsorptiometry method. The quantitative analysis focused on the location of the low-density area at the articular surface to assess potential osteochondral donor sites. RESULTS: All participants in the pitcher and fielder groups demonstrated a low-density area widely distributed in the proximal part of the lateral trochlea. On the other hand, a high-density area was located in the distal part of the lateral notch, of the medial notch, and of the medial trochlea. No apparent differences in the distribution pattern were found between the baseball groups and the control groups. CONCLUSION: Our analysis, based on CT osteoabsorptiometry, indicates that the proximal lateral trochlea of the distal femur has the highest percentage area of low bone density at the PF joint level in donor knees of baseball players, soccer players, and nonathlete controls. CLINICAL RELEVANCE: From a biomechanical viewpoint, the proximal lateral trochlea is the optimal site for harvesting osteochondral grafts in performing mosaicplasty for baseball players. This selection for the donor site may minimize postoperative PF joint symptoms.

In vivo vascularity alterations in repaired rotator cuffs determined by contrast-enhanced ultrasound.

BACKGROUND: The alterations in blood flow after rotator cuff repair remain unclear. Visualization of vascular patterns could clarify basic and clinical investigations. PURPOSE: To assess longitudinal blood flow inside the repaired cuff and the surrounding tissue after rotator cuff repair, using contrast-enhanced ultrasonography. STUDY DESIGN: Descriptive laboratory study. METHODS: Fifteen patients (7 men and 8 women; mean age, 65.0 ± 9.8 years) consented to participate. The patients underwent an ultrasound scan before and 1, 2, and 3 months after surgery. Enhanced ultrasound images were recorded for 1 minute after intravenous injection of contrast reagent. Four regions of interest inside the cuff and 2 regions in the anchor hole and subacromial bursa were superimposed on the obtained images. Calculated areas under the time-intensity curves were expressed in acoustic units (AU). RESULTS: We found area-dependent differences in patterns of alteration and magnitude of blood flow inside the repaired cuff and peritendinous tissues. Vascularity in the articular distal and bursal distal region of the repaired cuff at 1 month postoperatively increased significantly compared with that at the preoperative baseline (76 vs 5 AU, P = .0037; 92 vs 7 AU, P = .043). The vascularity peaked at 1 month after surgery in the bursal area within the cuff but at 2 months in the articular area. The vascularity in the articular proximal region of the repaired cuff was significantly lower than that in the bursal proximal (P = .0046), bursal distal (P = .0183), and articular distal regions (P = .0163) 1 month after surgery. CONCLUSION: Enhancement patterns in intratendinous tissue increased at 1 or 2 months postoperatively and decreased at 3 months. We found area-dependent differences in enhancement patterns inside the repaired cuff and peritendinous tissue. CLINICAL RELEVANCE: Visualization of vascularization using contrast-enhanced ultrasound could help in deciding on an appropriate repair technique or on the form of postoperative rehabilitation after rotator cuff repair.

Arthroscopic-assisted repair of avulsed triangular fibrocartilage complex to the fovea of the ulnar head: a 2- to 4-year follow-up study.

PURPOSE: The objective of this study was to conduct a follow-up evaluation of an arthroscopic reattachment technique using an avulsed deep component of the triangular fibrocartilage complex (dc-TFCC) from the fovea of the distal ulna (ulnar fovea). METHODS: A retrospective study was performed on a consecutive cohort of 12 patients who underwent arthroscopic reattachment of the avulsed dc-TFCC into the ulnar fovea over a 24-month period. The mean age was 31 years (range, 20 to 50 years). There were 6 men and 6 women. This technique anchors the avulsed portion of the dc-TFCC to the ulnar fovea by means of a repair suture passed through the created osseous tunnel from the ulnar neck to the foveal surface. Postoperative clinical and functional outcomes were quantitatively evaluated with the Modified Mayo Wrist Score. The Disabilities of the Arm, Shoulder and Hand questionnaire served to assess each patient's subjective outcome. A questionnaire regarding each patient's return to his or her previous job was also completed. Radiographic evaluation was based on computed tomography and magnetic resonance imaging examinations. RESULTS: At the mean follow-up of 30 months, all patients had significant reduction of wrist pain. The mean Modified Mayo Wrist Score was 92.5 ± 7.5, and all patients were rated as having excellent or good clinical results. The Disabilities of the Arm, Shoulder and Hand score significantly improved from 59.5 ± 18.5 to 7.7 ± 11.9 postoperatively (P < .0001). Of the 9 working patients, 7 returned to their previous work. Two patients had occasional extensor carpi ulnaris tendinitis after surgery. Magnetic resonance images at 12 weeks postoperatively showed findings indicating attachment of the triangular fibrocartilage complex (TFCC) to the fovea. CONCLUSIONS: Arthroscopic reattachment of the avulsed TFCC to the ulnar fovea by the described technique is a valid alternative for treating avulsion of the foveal TFCC insertion.

Covering the below-knee amputation stump with the pedicled dorsalis pedis flap from the ipsilateral foot: a case report.

It is important to preserve the length, appropriate durable skin, and sensation of the stump when performing below-knee amputation to achieve functional ambulation with a prosthesis. There are many reports of reconstruction procedures using microvascular surgery to preserve the optimum length of the amputation stump for prosthesis; however, free tissue reconstruction is necessary to accompany with the donor site morbidity. In this report, we describe our experience with a below-knee amputation and stump covering using the pedicled dorsalis pedis flap from the no longer usable foot in the case of a severe osteomyelitis of a lower extremity after highly contaminated Gustilo type IIIB fracture. We achieved a well-healed amputated stump with enough length for a prosthesis and for protective sensation. The pedicled dorsalis pedis flap is easily elevated without microvascular anastomosis and is one useful option for the reconstruction of the below-knee amputated stump in the specific case.

Giant-cell tumor of the distal ulna treated by wide resection and ulnar support reconstruction: a case report.

Giant-cell tumor of bone occurred in the distal end of the ulna is extremely uncommon. A 23-year-old male had a giant-cell tumor occurred in the distal end of the ulna. After wide resection of the distal segment of the ulna including giant-cell tumor, ulnar components of the wrist joint were reconstructed with modified Sauvé-Kapandji procedure using the iliac bone graft, preserving the triangular fibrocartilage complex and ulnar collateral ligament in order to maintain ulnar support of the wrist, and the proximal stump of the resected ulna was stabilized by tenodesis using the extensor carpi ulnaris tendon. One year after operation, the patient's wrist was pain-free and had a full range of motion. Postoperative X-rays showed no abnormal findings including recurrence of the giant-cell tumor and ulnar translation of the entire carpus. The stability of the proximal stump of the distal ulna was also maintained.

Palmar subluxation of the thumb carpometacarpal joint following the median nerve recurrent branch injury.

To our knowledge, the combination of a palmar subluxation of the thumb carpometacarpal (CMC) joint with low median nerve deficit followed by the recurrent branch injury is extremely rare. We present a case of the subluxation of the thumb CMC joint with low median nerve deficit.

Crystallization and preliminary crystallographic analysis of the Tob-hCaf1 complex.

The Tob/BTG family is a group of antiproliferative proteins that contain two highly homologous regions named Box A and Box B. These proteins all associate with CCR4-associated factor 1 (Caf1), which belongs to the ribonuclease D family of deadenylases. The antiproliferative region of human Tob (residues 1-138) and intact hCaf1 were co-expressed in Escherichia coli, purified and successfully cocrystallized. The crystal belongs to the tetragonal space group I422, with unit-cell parameters a = b = 150.9, c = 113.9 A, and is estimated to contain one heterodimer per asymmetric unit. The crystal diffracted to around 2.6 A resolution.