Establishment and characterization of a novel dedifferentiated chondrosarcoma cell line, SMU-DDCS, harboring an IDH1 mutation.

Dedifferentiated chondrosarcoma (DDCS) is a high-grade subtype with a bi-morphic histological appearance of a conventional chondrosarcoma component and it can abruptly transition to a high-grade non-cartilaginous sarcoma. To better understand the biological features of DDCSs and to help develop new therapies, a novel DDCS cell line, SMU-DDCS, was established. Tissue from an open biopsy of a tumor resected from a 75-year-old patient was subjected to primary culture. The cell line was established and authenticated by assessing DNA microsatellite short tandem repeats. The cells maintained in monolayer cultures exhibited constant growth, spheroid formation, and high invasive capacity. Out of the four mice inoculated with SMU-DDCS cells, tumors developed in three mice after 2 weeks. R132C mutation was found in the IDH1 but not the IDH2 genomic DNA sequence of SMU-DDCS cells. SMU-DDCS cells exhibited low chemosensitivity to doxorubicin, methotrexate, and cisplatin. This SMU-DDCS cell line harboring an IDH1 mutation will be a useful tool for investigating DDCS development and for evaluating novel therapeutic agents against it.

Innervated thenar pedicle flap with the palmar cutaneous branch of the median nerve for treating a thumb pulp defect: a case report.

A 51-year-old male plumber with a thumb pulp defect was treated with a reversed innervated thenar pedicle flap. The flap was based on the radial digital artery originating from the princeps pollicis artery with the palmar cutaneous branch of the median nerve. The flap survived and achieved good innervation with a moving 2-point discrimination of 6 mm at 12 months after surgery. This flap is indicated for patients who hesitate to have tissue taken from the foot. We believe that this flap is a feasible option for reconstructing thumb pulp defects.

Innervation pattern at the undersurface of the extensor carpi radialis brevis tendon in recalcitrant tennis elbow.

PURPOSE: We investigated the general, sensory, and sympathetic innervation patterns at the undersurface of the extensor carpi radialis brevis (ECRB) origin in patients with recalcitrant tennis elbow. METHODS: Eight elbows in eight consecutive patients (6 females and 2 males) with tennis elbow who underwent arthroscopic surgery were included in this study. The mean age was 45 years (38-66 years), and the mean duration of symptoms before surgery was 23 months (13-52 months). Operative treatment consisted of an arthroscopic inspection and debridement of the ECRB origin. Control tissues were obtained from biopsy of the ECRB capsule in two patients with osteochondritis dissecance of the capitellum who underwent arthroscopic resection of loose bodies. The tissue specimens were investigated immunohistochemically with antibodies delineating general (PGP9.5), sensory (SP/CGRP), and sympathetic (NPY) nerve patterns. RESULTS: In the non-tendinosis control tissue, SP/CGRP and NPY immunoreactions were heterogeneously distributed in association with blood vessels. Pathologic evaluation of the biopsy tissue showed atypical fibrous granulation containing numerous vessels and nerve structures in all eight patients. Marked reactions to PGP 9.5 took the form of nerve fibers associated with arteries and arterioles in the atypical granulation. Most of the perivascular innervation was found to express NPY. The immunoreactions for SP and CGRP were invariably weak. CONCLUSION: Increased perivascular sympathetic innervation accompanied with loss of sensory innervation at the undersurface of the ECRB tendon may play a role in chronic pain generation in recalcitrant tennis elbow. LEVEL OF EVIDENCE: Diagnostic, Level IV.

Nonunion of the ulnar styloid associated with distal radius malunion.

PURPOSE: Malunion is a complication of distal radius fractures and may be associated with a nonunion of the ulnar styloid. We tested the null hypothesis that there is no difference in outcome between patients without ulnar styloid fracture and those with the ulnar styloid nonunion after corrective radial osteotomy for distal radius malunion. METHODS: A total of 19 patients with dorsally angulated distal radius malunion who had simultaneous radial closing-wedge and ulnar shortening osteotomies were included. There were 16 women and 3 men with a mean age of 63 years. All patients were followed up for a minimum of 1 year. During surgery, the accompanying ulnar styloid nonunion was not internally fixed in any patient. Eight patients had no ulnar styloid fracture, and 11 had a nonunion of the ulnar styloid. Each group of patients was evaluated on the basis of objective radiographic measurements and functional outcomes as determined on the basis of clinical examination, including wrist motion, grip strength, pain-rating score, Mayo wrist score, and Disabilities of the Arm, Shoulder, and Hand score. RESULTS: There were no differences in the demographic and preoperative radiographic measurements between the nonfracture and nonunion groups. Postoperative radiographic measurements and functional outcomes improved significantly compared with the preoperative status in both groups. There were no significant differences in postoperative radiographic measurements, motion, strength, pain scores, Mayo scores, or Disabilities of the Arm, Shoulder, and Hand scores between the 2 groups. Four of the 11 ulnar styloid nonunions were healed within 1 to 12 months after corrective radial osteotomy. CONCLUSIONS: An accompanying ulnar styloid nonunion in patients with distal radius malunion has no apparent adverse effect on outcome or function after corrective radial osteotomy. An accompanying nonunion of the ulnar styloid can heal following corrective radial osteotomy.

Metallothionein deficiency in the injured peripheral nerves of complex regional pain syndrome as revealed by proteomics.

Complex regional pain syndrome (CRPS) is characterized by persistent and severe pain after trauma or surgery; however, its molecular mechanisms in the peripheral nervous system are poorly understood. Using proteomics, we investigated whether injured peripheral nerves of CRPS patients have altered protein profiles compared with control nerves. We obtained nerve samples from 3 patients with CRPS-2 who underwent resection of part of an injured peripheral nerve. Sural nerves from fresh cadavers with no history of trauma or neuropathic pain served as controls. Proteomic analysis showed that the number and functional distribution of proteins expressed in CRPS and control nerves was similar. Interestingly, metallothionein was absent in the injured nerves of CRPS-2, although it was readily detected in control nerves. Western blotting further confirmed the absence of metallothionein in CRPS-2 nerves, and immunohistochemistry corroborated the deficiency of metallothionein expression in injured nerves from 5 of 5 CRPS patients and 2 of 2 patients with painful neuromas. In contrast, all control nerves, including 5 sural nerves from fresh cadavers and 41 nerves obtained from surgically resected tumors, expressed MT. Furthermore, expression of S100 as a marker for Schwann cells, and neurofilament M as a marker of axons was comparable in both CRPS-2 and controls. Metallothioneins are zinc-binding proteins that are probably involved in protection against injury and subsequent regeneration after CNS damage. Their absence from the injured peripheral nerves of patients with CRPS-2 suggests a potential pathogenic role in generating pain in the damaged peripheral nerves.

The detection of the capsular tear at the undersurface of the extensor carpi radialis brevis tendon in chronic tennis elbow: the value of magnetic resonance imaging and computed tomography arthrography.

HYPOTHESIS: This study compared the diagnostic efficacy of magnetic resonance imaging (MRI) and computed tomography arthrography (CTA) in the assessment of capsular tears at the undersurface of the extensor carpi radials brevis tendon in chronic tennis elbow using arthroscopy as a gold standard. Because of the higher spatial resolution of CT, we hypothesized that CTA is superior to MRI for assessing capsular tears. MATERIALS AND METHODS: We retrospectively reviewed 19 consecutive patients with chronic tennis elbow with preoperative MRI and CTA studies who underwent arthroscopic surgery. Three observers with different levels of training and experience (musculoskeletal radiologist, experienced elbow surgeon, and hand fellow) evaluated the capsular tear by MRI and CTA in a blinded manner. The results of the MRI and CTA were compared and the agreement among the 3 observers was determined using an intraclass correlation coefficient (ICC). Then, the results of the MRI and CTA examinations were compared with the intraoperative findings of the arthroscopic examination. The sensitivity, specificity, and κ value were calculated. RESULTS: The ICC of CTA (0.855) was superior to MRI (0.645). The sensitivity, specificity, and κ value of CTA were superior to those of MRI in each of the 3 observers. The κ value was 0.79, 0.89, and 0.79 for CTA, and 0.48, 0.48, and 0.27 for MRI for the radiologist, surgeon, and fellow, respectively. CONCLUSIONS: CTA was a reliable and accurate diagnostic modality compared with MRI to detect the capsular tear in patients with chronic tennis elbow. CTA was less influenced by the observer's experience.

Functional outcomes after arthroscopic treatment of lateral epicondylitis.

BACKGROUND: The purpose of this study was to evaluate surgical outcomes of arthroscopic débridement for lateral epicondylitis using a validated, patient-assessed scoring system as well as conventional outcome measures. We also wanted to identify potential predictive factors that may be associated with the outcomes. METHODS: A total of 20 elbows in 18 patients with chronic lateral epicondylitis who underwent arthroscopic surgery were included. There were nine men and nine women with a mean age of 54 years (range 42-71 years). Operative treatment consisted of débridement of the extensor carpi radialis brevis (ECRB) origin and resection of the radiocapitellar synovial plica interposed in the joint. Outcomes were assessed using a patient rating, visual analogue scale (VAS) pain score, the Japanese Orthopaedic Association (JOA) elbow score, and the Disability of the Arm, Shoulder, and Hand (DASH) questionnaire. The average length of follow-up was 28 months (range 24-40 months). RESULTS: After surgery, according to the patients' reports, 14 of 20 elbows were much better, and 6 elbows were better. A mean preoperative VAS pain score at rest of 3.9 points improved to 0.3 points (P < 0.0001), and that during activity improved from 7.8 points to 0.9 points (P < 0.0001). The mean preoperative JOA elbow score of 29 points was improved to 90 points (P < 0.0001). The mean postoperative DASH score was 10.6 (range 0-50). Absent of T2-weighted high signal focus of the ECRB origin on preoperative magnetic resonance imaging (MRI) (P = 0.02) and receiving public assistance (P = 0.01) were significantly associated with worse DASH scores. CONCLUSIONS: Arthroscopic release was a satisfactory procedure for chronic lateral epicondylitis. Preoperative MRI of the ECRB origin and socioeconomic factors were significantly associated with postoperative residual symptoms evaluated with the DASH score.

Arthroscopic, macroscopic, and microscopic anatomy of the synovial fold of the elbow joint in correlation with the common extensor origin.

PURPOSE: The objective of our study was to clarify the arthroscopic, macroscopic, and microscopic anatomy of the radiocapitellar synovial fold of the elbow joint in correlation with the common extensor origin. METHODS: We performed arthroscopy in 14 fresh-frozen cadaveric elbows and found the synovial fold covering the radial head or interposing in the radiocapitellar joint in 6. The fold was tagged with loop suture under arthroscopy to identify its exact location in gross anatomy. The radiocapitellar joint capsule was then resected without disturbing the continuity of the common extensor and lateral epicondyle. Macroscopic and histologic evaluation was performed for the lateral elbow capsular complex. RESULTS: The synovial fold was found to be a triangular-shaped thickening of the capsule located on the proximal edge of the annular ligament. The mean distance between the lateral epicondyle and the base of the fold at the anterior edge, middle part, and posterior edge was 23 mm, 8 mm, and 13 mm, respectively. This structure was distinct from the annular ligament but was continuous with the radiocapitellar joint capsule. The joint capsule and the common extensor tendon blended with each other imperceptibly and formed a single enthesis at the lateral epicondyle. CONCLUSIONS: The synovial fold identified by arthroscopy is a physiologic capsular tissue located on the proximal edge of the annular ligament. It is distinct from the annular ligament but has a close correlation with the common extensor tendon enthesis at the lateral epicondyle. CLINICAL RELEVANCE: The synovial fold belongs to the lateral epicondyle enthesis, which is a composite of the common extensor tendon, undersurface capsule, and bone. Therefore, lateral epicondylitis with degenerative lesions in the area of the common extensor origin may involve the synovial fold and induce hypertrophic changes.

Simultaneous radial closing wedge and ulnar shortening osteotomy for distal radius malunion.

Closing wedge osteotomies are an attractive treatment option for distal radius malunion in patients with osteopenia. It does not require a separate-site bone graft, result-ing in decreased morbidity. However, this procedure has always been performed in combination with ulnar head resection to accommodate closure of corrective osteotomy and to address the issue of ulnocarpal abutment. Because ulnar shortening osteotomy is more physiological solution, it seemed advantageous to us to combine radial closing wedge osteotomy and ulnar shortening osteotomy. In this article, we present in detail our technique for treating patients with distal radius malunion. The patients are potentially osteopenic such as women aged over 45 years and are active at home, work, and/or recreation but are not involved in heavy physical work. Through volar approach an appropriate bone wedge is removed from the distal radius. A small volar T-plate is used to secure the osteotomized bone fragments. The aim of the radial osteotomy is to correct the dorsal angulation in the sagittal plane within a normal range of 1 degree to 2 degrees with reference to that of opposite wrist. Ulnar shortening osteotomy is performed by using transverse osteotomy and compression plating technique with an AO compression device. The ulnar variance is adjusted to neutral. Although the technique presented requires the surgeons to use careful plate and screw technique, early results have been encouraging, and patients with osteopenia can be treated successfully. Decreased grip strength which may be provoked by shorting of the forearm is acceptable.

[QOL in osteoporotic patients with vertebral fractures].

Vertebral fractures leading to low back pain, spinal deformity, gastroesophageal reflux disease, and cardiopulmonary dysfunctions decrease the quality of life (QOL) in patients with osteoporosis. We had investigated the change of QOL in osteoporosis patients with back pain for 6 months. The relief of the pain improved "activities of daily living" , but did not "leisure, social activities" , "health perception" , "posture, figure" , and "fall, mental factors" . The control of pain and social approach such as fall prevention program are necessary to improve the QOL in patients with vertebral fractures.