Effectiveness of filling structures within nerve guidance conduits in a rat sciatic nerve injury model.

Introduction: The gold standard treatment for peripheral nerve gap injury is nerve autograft transplantation. Although various nerve guidance conduits (NGCs) have been developed as alternatives to autografting, few reports have evaluated the effects of the internal structure of NGCs on nerve regeneration. We investigated how the internal structure of NGCs affects nerve regeneration.

Comprehensive Elbow Joint Morphology Changes in Surgically Treated Osteochondritis Dissecans of the Capitellum: Clinical Implications.

Background: Capitellar osteochondritis dissecans (OCD) frequently results in radial head enlargement. However, due to the elbow joint's complex anatomy, deformities likely extend beyond just the radial head.

Hypothesis/purpose: It was hypothesized that in patients with OCD treated with surgery, imbalances in bone morphology during growth would affect the entire joint, leading to postoperative clinical symptoms.

Simultaneous Intra-articular and Extra-articular Corrective Osteotomies Using a Patient-Matched Surgical Guide and Plate for Malunion After Distal Radius Fractures: A Report of Two Cases.

Malunion after distal radial fractures with intra-articular and extra-articular deformities is difficult to treat. We report two cases of simultaneous intra-articular and extra-articular corrective osteotomies for malunion after distal radius fractures using a patient-matched surgical guide and plate (patient-matched instruments [PMIs]) created based on a preoperative computer simulation. Both patients experienced pain and limited range of motion in the wrist and forearm.

Neurotropin® alleviates nerve damage in a mouse chronic nerve compression model.

Chronic nerve compression disorders, such as carpal tunnel syndrome, are common and can significantly impair daily activities due to motor and sensory dysfunctions. Currently, no systemic pharmacotherapy exists for preventing or treating disease progression. This study aims to investigate whether Neurotropin®, an established analgesic, has therapeutic effects.

Methylcobalamin-containing nanofiber sheets have better neuroprotective effects than small intestinal submucosa sheets.

Postoperative adhesion around nerves sometimes results in sensory and motor dysfunctions. To prevent these disorders, we have developed an electrospun nanofiber sheet incorporating methylcobalamin (MeCbl), an active form of vitamin B12 with anti-inflammatory and neuroregenerative effects. This study aimed to investigate the neuroprotective effects of MeCbl sheets against postoperative adhesion and to compare the effects of MeCbl sheets with those of porcine small intestinal submucosa (SIS) sheets using a rat sciatic nerve adhesion model.

Estimating elbow loading conditions through the motion behaviors of subchondral bone density during joint movements.

Evaluating complicated stress across the elbow under joint motion remains difficult. Here, we aimed to evaluate the distribution of the subchondral bone density in the normal elbow bones and further characterize their spatial relationships during elbow motion to estimate the loading stress across the articular surface using three-dimensional computed tomography bone models. The normal elbow joint exhibited a consistent distribution pattern of subchondral bone density.

Association of dorsal malunion in distal radius fractures with wrist osteoarthritis: Alterations of bone density and stress-distribution patterns in relation to deformation angles.

Objective: Distal radius fractures (DRFs) with dorsal malunion increase the risk of osteoarthritis (OA), although the cause of post-DRF OA is yet to be elucidated. To clarify the abnormal effects of a post-DRF dorsal radius deformity, we evaluated the bone density (BD) and stress-distribution patterns of the articular surface in dorsally malunited DRFs.

Design: In 36 cases of dorsally malunited DRFs following extra-articular fractures, we generated three-dimensional computerized models of the malunited distal radius from computed tomography data and extracted the subchondral bones of the radiocarpal joint (RCJ) and distal radioulnar joint (DRUJ).

Intra-Articular Corrective Osteotomy for Distal Radial Intra-Articular Malunion Using Patient-Matched Instruments: A Prospective, Multicenter, Open-Label, Single-Arm Trial.

Background: Corrective osteotomy for intra-articular malunion is a challenging procedure. However, recent advancements, including patient-matched instruments created on the basis of preoperative computer simulation, enable accurate intra-articular correction. We hypothesized that intra-articular corrective osteotomy using patient-matched instruments for the treatment of distal radial intra-articular malunion would reduce intra-articular deformity and restore wrist function at 12 months of follow-up.

Cubitus varus deformity following paediatric supracondylar humeral fracture remodelling predominantly in the sagittal direction: A three-dimensional analysis of eighty-six cases.

Purpose: Three-dimensional (3D) capacity for remodelling in cubitus varus deformity (CVD) after paediatric supracondylar humeral fractures (PSHFs) remains unelucidated. This study investigated remodelling patterns after PSHFs by examining 3D deformity distribution over time after injury.

Methods: Computed tomography (CT) data of 86 patients with CVD after PSHFs were analysed.

The effect of forearm rotation on the bone mineral density measurements of the distal radius.

Introduction: Forearm dual-energy X-ray absorptiometry (DXA) is often performed in clinics where central DXA is unavailable. Accurate bone mineral density (BMD) measurement is crucial for clinical assessment. Forearm rotation can affect BMD measurements, but this effect remains uncertain.

Quantitative 3-D CT Demonstrates Distal Row Pronation and Translation and Radiolunate Arthritis in the SNAC Wrist.

Background: In scaphoid nonunion advanced collapse (SNAC) wrist arthritis, we analyzed the 3-dimensional (3-D) deformity patterns of carpal alignment secondary to scaphoid nonunion and quantified subchondral arthritis by investigating alterations in bone density.

Methods: We constructed 3-D models of the carpal bones and radius from 51 patients with scaphoid nonunion (nonunion group) and 50 healthy controls (control group). We quantified the differences in 3-D geometric position of the distal carpal row relative to the distal radius in SNAC wrists versus controls.

Risk of nerve injury during elbow arthroscopy: ultrasonographic evaluation of preoperative patients.

Background: To clarify the real risk of nerve injury during elbow arthroscopy, the distances of the radial and median nerves to the elbow joint were investigated using ultrasonography in patients who underwent surgery.

Methods: A total of 35 patients who underwent arthroscopic surgery of the elbow were investigated. The distances of the nerves to the capsule and bony landmarks were measured using ultrasonography.

Arthroscopic Debridement for Refractory Lateral Epicondylitis Results for Substantial Improvement in Tendinosis Scores and Good Clinical Outcomes: Qualitative and Quantitative Magnetic Resonance Imaging Analysis.

Purpose: To qualify and quantify the changes in magnetic resonance imaging (MRI) signals in the extensor tendons after arthroscopic debridement for lateral epicondylitis and evaluate the association between MRI findings and temporal clinical results by comparisons between recovered and unrecovered cases.

Methods: Thirty-four patients with refractory lateral epicondylitis treated with arthroscopic debridement were divided into recovered (n = 24) and unrecovered (n = 10) groups according to the Japanese Orthopaedic Association-Japan Elbow Society score. This study included any patients who underwent both the pre- and postoperative MRI and excluded patients with a previous history of any elbow surgery.

Patient-Reported Outcomes After Surgical Treatment of Early Osteoarthritis of the First Carpometacarpal Joint.

Background: The goals of this study are to describe the reoperation rates in patients who underwent Wilson osteotomy compared with patients who underwent carpometacarpal (CMC) arthroplasty for early-stage arthritis and to evaluate the factors influencing the patient-reported outcomes.

Methods: Retrospectively, 52 patients who underwent surgery for stage I/II osteoarthritis of the thumb carpometacarpal were identified, consisting of 17 (33%) patients who underwent Wilson osteotomy and 35 (67%) who underwent carpometacarpal arthroplasty. A total of 28 (55%) patients completed the outcome questionnaires, consisting of 11 (39%) patients who underwent Wilson osteotomy and 17 (61%) patients who underwent carpometacarpal arthroplasty.

Arthroscopic Debridement of Elbow Osteoarthritis Using CT-Based Computer-Aided Navigation Systems Is Accurate.

Purpose: To evaluate whether the bony impingement lesion in elbow osteoarthritis can be removed accurately, as planned during arthroscopy, by using the computer-aided navigation system and performing mock surgery using 3-dimensional (3D)-printed bone models for clinical applications.

Methods: We performed mock surgery using 3D-printed plaster bone models of the humerus of 15 actual patients with elbow osteoarthritis. Two types of experiments were conducted to evaluate the surgical accuracy.

Soft-tissue coverage for wound complications following total elbow arthroplasty.

Background: In patients with total elbow arthroplasty (TEA), the soft-tissue around the elbow can be vulnerable to soft-tissue complications. This study aims to assess the outcomes after soft-tissue reconstruction following TEA.

Methods: We retrospectively included nine adult patients who underwent soft-tissue reconstruction following TEA.

A Quantitative Analysis of Subchondral Bone Density Around Osteochondritis Dissecans Lesions of the Capitellum.

Purpose: In capitellar osteochondritis dissecans (OCD), unstable lesions generally demonstrate signs of subchondral sclerosis. We postulate that OCD lesions have abnormal subchondral bone density. We aimed to quantify the subchondral bone thickness around OCD lesions using conventional computed tomography (CT) imaging.

Degenerative changes in the elbow joint after radial head excision for fracture: quantitative 3-dimensional analysis of bone density, stress distribution, and bone morphology.

Hypothesis And Background: Some investigators speculate that excision may lead to elbow arthritis and associated problems; however, evidence supporting this theory is limited. It is hypothesized that radial head excision causes bone density changes as a result of asymmetrical stress distributions, consequently leading to osteophyte formation. In this study, we sought to quantitatively compare the 3-dimensional (3D) bone density and stress distributions between operative and nonoperative elbows in patients who underwent radial head excision.

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.