Prognostic factors and clinical features in metacarpophalangeal joint hyperextension after ligament reconstruction with trapeziectomy: A retrospective cohort study.

BACKGROUND: Management of metacarpophalangeal (MCP) hyperextension deformity in thumb carpometacarpal (CMC) joint arthritis is challenging. It remains unclear how the preoperative MCP joint angle affects the outcomes. The present study aimed to clarify the associations between postoperative MCP hyperextension deformity and outcomes, and to determine the preoperative MCP joint angle that can predict poor outcomes. METHODS: We investigated the functional outcomes of patients who underwent surgery for CMC arthritis at two institutions from 2016 to 2020. All patients received a modified Thompson technique, ligament reconstruction suspension arthroplasty, and had no additional treatment for MCP hyperextension. The patients were divided into three groups according to their postoperative MCP joint angles: Group A, <10°; Group B, 10°-20°; Group C, >20°. Evaluations included preoperative and postoperative VAS, Quick DASH, range of motion (ROM), grip power, pinch strength, first web space angle, and postoperative trapezial space ratio (TSR). RESULTS: Overall, 66 eligible patients (72 thumbs) were identified and received follow-up for a mean of 25.2 months. The 72 thumbs were assigned to Group A (n = 38), Group B (n = 16), and Group C (n = 18). Group C had significantly lower preoperative MCP joint angle and postoperative grip power, pinch strength, and TSR compared with the Group A (P < 0.05). However, there were no significant differences in VAS, Quick DASH, ROM, and first web space angle (P > 0.05). The preoperative risk factor for highly residual MCP hyperextension was preoperative MCP joint angle (OR = 1.078; P = 0.001), with a cut-off value of 21.5° (AUC = 0.79; sensitivity = 0.813; specificity = 0.821). CONCLUSIONS: Postoperative MCP hyperextension of >20° after ligament reconstruction with trapeziectomy has adverse effects on functional outcomes. In cases with preoperative MCP joint angle of >21.5°, additional treatment for MCP hyperextension should be considered.

Suspension arthroplasty using the palmaris longus tendon with a suture button for thumb trapeziometacarpal arthritis: a retrospective observational study.

BACKGROUND: This study was performed to assess the clinical and radiographic results at a minimum of 2 years after ligament reconstruction suspension arthroplasty (LRSA) that comprised full trapeziectomy and suspensionplasty using the palmaris longus tendon and the Mini TightRope (Arthrex, Naples, FL) for advanced thumb carpometacarpal arthritis. METHODS: We clinically and radiographically evaluated 26 thumbs in 26 patients who had undergone LRSA at least 2 years previously. The mean follow-up period was 35.9 months. We evaluated the subjective clinical outcomes (visual analogue scale and Quick Disabilities of the Arm, Shoulder, and Hand scores) and objective clinical outcomes (range of motion, pinch strength, grip strength, and trapezial space height ratio). RESULTS: At the final follow-up evaluation, the mean visual analogue scale score was 11.1 (standard deviation (SD) 13.4) and the mean Quick Disabilities of the Arm, Shoulder, and Hand questionnaire score was 9.39 (SD 10.1). The mean palmar and radial abduction were 62.3° (SD 11.8°) and 63.8° (SD 9.09°), respectively. The mean key pinch and grip strength were 3.92 (SD 1.07) kg and 19.7 (SD 7.77) kg, respectively. The mean trapezial space ratio was 0.21 (SD 0.10). The subjective clinical outcomes, range of motion, and pinch strength were significantly improved compared with preoperatively. CONCLUSIONS: LRSA for advanced-stage thumb carpometacarpal osteoarthritis relieves pain, improves range of motion and strength, and obtains favourable subjective patient-reported clinical outcomes.

Analysis of medialisation of the femoral head in periacetabular osteotomy using three-dimensional computed tomography.

BACKGROUND: Periacetabular osteotomy has been established as an effective treatment for osteoarthritis caused by developmental dysplasia of the hip. Medialisation of the femoral head during periacetabular osteotomy is crucial for providing significant reduction in joint contact stress. The purpose of this study was to evaluate effective procedures for medialisation of the femoral head during periacetabular osteotomy using three-dimensional computed tomography (3DCT). METHODS: Thirty hips in 30 patients with hip dysplasia underwent both radiographic and 3DCT scans before and after surgery. The direction of the rotation of the acetabular fragment and movement of the femoral head were evaluated to analyse which parameters contributed to medialisation of the femoral head. RESULTS: Anterior coverage of the acetabular fragment and internal rotation in the axial plane contributed to both medialisation of the femoral head and anteversion of the retroverted acetabulum. CONCLUSIONS: This study demonstrated that re-orientation of the acetabulum was spatially confirmed by the method using 3DCT images.

Painless angioleiomyoma of the first web space of the hand.

Angioleiomyoma is a benign dermal or subcutaneous tumor originating from the tunica media of small veins and arteries, and rarely occurs in the hand. Because of its non-specific imaging features, a definite preoperative diagnosis is quite difficult. We present an unusual case of angioleiomyoma arising in the first web space of the right hand of a 56-year-old male. Physical examination showed a 3-cm, elastic-soft, mobile, non-tender mass. Magnetic resonance imaging (MRI) revealed a well-demarcated, subcutaneous, soft tissue mass with iso- to slightly high signal intensity relative to skeletal muscle on T1-weighted sequences and heterogenous high signal intensity with scattered foci of low signal intensity on T2-weigthed sequences. Contrast-enhanced fat-suppressed T1-weighted sequences demonstrated heterogenous, strong enhancement throughout the mass. There was no vascular structure closely abutting the mass. Simple excision of the mass was performed, and the histology was characteristic of an angioleiomyoma. The patient had no evidence of local recurrence within four months of follow-up. Angioleiomyoma should be considered in the differential diagnosis of a well-defined, oval soft tissue mass in the first web space of the hand even when an adjacent tortuous vascular structure is not seen on MRI.

Quantitative (19)F imaging of nmol-level F-nucleotides/-sides from 5-FU with T(2) mapping in mice at 9.4T.

A unique acquisition method is proposed for quantitative, high-sensitivity (19)F MR spectroscopic imaging for the study of drug distribution aiming at nmol-level metabolite information in mice. The use of fast spin echo (FSE) at 9.4T allowed us to obtain whole-body images with minimal effect of magnetic susceptibility and to acquire several metabolite signals simultaneously by the method of interleaved multifrequency selection. Modified 2-shot FSE was designed for simultaneous, high-sensitivity (19)F imaging and T(2) mapping. A time course study including all the main metabolites at 10-minute resolution was attained with an oral dose of 1-2 mmol 5-fluorouracil (5-FU) (130-260 mg)/kg in mice. With acquisition parameters optimized for in vivo T(2) of 40 ms, images of F-nucleotides/-sides, effective anabolites of the anticancer drug 5-FU, were obtained at the level of 200 nmol in the tumor for all the mice studied with a linear correlation (R = 0.96) between image intensity and the quantity determined in the excised tissue. The method exhibits potential capability of molecular imaging with a variety of (19)F-labeled compounds and drug evaluation.

Analysis of internal motions of RNase T1 complexed with a productive substrate involving 15N NMR relaxation measurements.

The backbone dynamics of RNase T1 in the presence of exo-guanosine 2',3'-cyclophosphorothioate (exo-cGPS isomer), which is a productive substrate, and in the presence of 3'-guanylic acid (3'GMP), which is an nonproductive substrate, were examined using (15)N nuclear magnetic resonance. Although the X-ray crystal structure suggests that the modes of binding of these substrates to the active-site cleft are very similar, the order parameters in a number of regions in RNase T1 complexed with exo-cGPS isomer were different from those with 3'GMP. Moreover, the chemical exchange in line width observed for RNase T1 complexed with exo-cGPS isomer was also different from that observed for RNase T1 complexed with 3'GMP. From these results, we concluded that the internal motions in RNase T1 complexed with a productive substrate were not always identical to those in RNase T1 complexed with a nonproductive substrate.

Determination of the secondary structure in solution of the Escherichia coli DnaA DNA-binding domain.

DnaA protein binds specifically to a group of binding sites collectively called as DnaA boxes within the bacterial replication origin to induce local unwinding of duplex DNA. The DNA-binding domain of DnaA, domain IV, comprises the C-terminal 94 amino acid residues of the protein. We overproduced and purified a protein containing only this domain plus a methionine residue. This protein was stable as a monomer and maintained DnaA box-specific binding activity. We then analyzed its solution structure by CD spectrum and heteronuclear multi-dimensional NMR experiments. We established extensive assignments of the 1H, 13C, and 15N nuclei, and revealed by obtaining combined analyses of chemical shift index and NOE connectivities that DnaA domain IV contains six alpha-helices and no beta-sheets, consistent with results of CD analysis. Mutations known to reduce DnaA box-binding activity were specifically located in or near two of the alpha-helices. These findings indicate that the DNA-binding fold of DnaA domain IV is unique among origin-binding proteins.