Changes in the Functional Range of Motion of the Thumb Metacarpophalangeal Joint After Trapeziometacarpal Arthrodesis for Patients With Advanced Trapeziometacarpal Osteoarthritis.

PURPOSE: Advanced-stage trapeziometacarpal (TMC) osteoarthritis of the thumb often presents with concomitant hyperextension deformity of the metacarpophalangeal (MCP) joint. Although several studies have reported simultaneous procedures to correct this deformity, the indication for these procedures remains controversial. The purpose of this study was to evaluate changes in the range of motion (ROM) of the thumb MCP joint before and after TMC arthrodesis. METHODS: We evaluated the functional flexion and extension and functional ROM of the MCP joints during the performance of 10 activities of daily living tasks before and after TMC arthrodesis in 10 thumbs of 9 patients with Eaton stage III TMC osteoarthritis and hyperextension deformity of the MCP joint. RESULTS: The mean functional flexion of the MCP joint increased from 26° to 38°, and the mean functional extension of the MCP joint decreased from 16° to 5° of hyperextension. There was no change in the mean total arc of functional ROM of the MCP joint. CONCLUSIONS: The MCP joint motion shifted from extension to flexion after TMC arthrodesis, and the total arc of functional ROM of the MCP joint was similar before and after arthrodesis. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic V.

Magnetic resonance imaging of diffusion characteristics following collagenase clostridium histolyticum injection in Dupuytren's contracture.

PurposeWe aimed to evaluate the extent of collagenase clostridium histolyticum (CCH) diffusion in Dupuytren's contracture (DC) for tissues outside of the contracture cord using Magnetic Resonance Imaging (MRI) immediately after CCH injection. Methods: 10 male patients aged 57-79 with DC of the metacarpophalangeal (MCP) joints were examined. Extension deficits were 10-60°(mean, 34.3) and 0-60°(mean, 26.6) in the MCP and proximal interphalangeal (PIP) joints, respectively. CCH injection was performed according to the standard method. MRI was performed within 15 min of CCH injection. Results: In all 10 cases, the extended area of high-intensity signal change outside of the cord was observed on short-T1 inversion recovery images (STIRs). Continuity from the insertion site was observed in the area of signal change involving the flexor tendon and neurovascular bundle. The signal change area spanned distally and proximally beyond the injection level. The signal change area expanded along the tendon sheath but no signal changes were observed inside the flexor tendon, suggesting the tendon sheath serves as a protective barrier from the CCH solution. After 1 week of injection, the mean decrease in contracture was 32.5°(94.7%) for the MCP joint and 19.8°(74.4%) for the PIP joint. In nine out of 10 cases, the extension deficit was within five degrees of full extension in the affected finger. There was no neurovascular injury or tendon rupture at 3 months of observation. Conclusions: MRI indicated the possible leakage of the drug outside of the cord during the early phase after administration, suggesting that CCH could persistently affect healthy tissues until CCH inactivates its enzyme process.

ZMAT2, a newly-identified potential disease-causing gene in congenital radioulnar synostosis, modulates BMP signaling.

Congenital radioulnar synostosis (RUS) is a rare skeletal disorder that is characterized by fusion of the radius and ulna. As the etiology of RUS is largely unknown, its treatment options are currently limited. A de novo missense mutation in the zinc finger matrin-type 2 (ZMAT2) gene was newly identified in a 5-year-old boy with RUS using whole-exome sequencing. Herein, we sought to further explore the function of zmat2 in zebrafish. Whole-mount in situ hybridization revealed site-specific expression of zzmat2 in the pectoral fins (equivalent to human upper limbs) and craniofacial regions, while immunohistochemistry showed the expression of zZmat2 in the pectoral fins and heart region. Gene knockdown produced defects in the pectoral fins and dorso-ventral patterning. zzmat2 knockdown also caused embryo dorsalization, a phenotype consistent with reduced/insufficient bone morphogenetic protein (BMP) signaling. These abnormalities were partially rescued by zbmp2b RNA overexpression and fully rescued by simultaneous overexpression of wild-type zzmat2. Importantly, the overexpression of mutant zzmat2 corresponding to the newly-identified mutation did not fully rescue the dorso-ventral patterning defects. The above findings indicate that ZMAT2 regulates skeletal development via the BMP signaling pathway, and its mutation may lead to a loss or reduction in biological activity. Thus, the newly identified ZMAT2 mutation potentially plays a causal role in RUS through deregulation of BMP signaling.

Pathological Findings of Hourglass-Like Constriction in Spontaneous Posterior Interosseous Nerve Palsy.

We report the pathological findings of hourglass-like fascicular constriction (HLFC) under optical and electron microscopy. A 24-year-old man with spontaneous posterior interosseous nerve palsy was treated by interfascicular neurolysis at 29 weeks after onset. One fascicle in the radial nerve presented severe HLFC with torsion at 5 cm proximal to the elbow. Functional recovery was achieved by resection of the enlarged fascicle including HLFC and sural nerve grafting. Proximal to the HLFC, the endoneurium was filled with clusters of regenerating nerve fibers. At the level of the HLFC, a complete loss of myelinated nerve fibers and vascular occlusion of endo- and perineurial vessels were found. Few regenerating nerve fibers were observed. Distal to the HLFC, severe endoneurial edema, a complete loss of myelinated and unmyelinated nerve fibers, and bands of Büngner were noted. These electron microscopic findings demonstrated a detailed pathology of the nerve around the HLFC.

Bone Peg Grafting for Capitellar Osteochondritis Dissecans in Adolescent Baseball Players.

BACKGROUND: Capitellar osteochondritis dissecans (OCD) is a focal injury of the articular cartilage involving separation of a segment of cartilage from the subchondral bone that is infrequently encountered in the dominant-side elbow of adolescent throwing athletes1,2. The literature suggests that patients may achieve better short and mid-term results when treated with certain types of surgical procedures3,4. Selection of the appropriate surgical method should be based on the International Cartilage Repair Society (ICRS) OCD classification system5. For lesions involving ≤50% of the surface area of the capitellum, debridement with microfracture and/or loose body removal have shown excellent results. For lesions involving >50% of the surface area of the capitellum and classified as ICRS OCD III or IV, autologous osteochondral grafting may be the most suitable treatment6-8. Bone peg grafting (BPG) has been shown to be an effective treatment option for early-stage capitellar OCD that can preserve the local hyaline cartilage9,10. DESCRIPTION: Using direct vision and with arthroscopy, the continuity of the capitellar surface and the stability of the capitellar lesion were evaluated according to the ICRS OCD classification5. BPG was indicated for adolescents with ICRS OCD I or II. The elbow was opened between the extensor carpi ulnaris and the anconeus muscle (Kocher interval). Another skin incision of 3 cm in length was made at the posterior aspect of the metaphysis of the ipsilateral olecranon. Three, 4, or 5 bone pegs of approximately 20 mm in length were harvested from the posterior ulnar cortex. A Kirschner wire of 3 mm in diameter was used for drilling holes in the lesion, and then the bone pegs were inserted with tweezers to a depth of 10 mm. Next, a flat-surfaced rod was placed on the head of each bone peg to press it to a depth slightly lower than the articular cartilage surface. Postoperatively, the elbow was immobilized for 3 weeks. Throwing was allowed at 6 months, and a return to competitive baseball at preinjury levels was permitted at 8 months after BPG. ALTERNATIVES: Arthroscopic debridement of the lesion.Arthroscopic bone marrow stimulation or microfracture.Fragment fixation using metal implants or biodegradable materials.Use of autologous osteochondral graft from the distal aspect of the femur or from a rib. RATIONALE: Our follow-up study after BPG revealed that 10 of 11 patients with ICRS OCD I or II capitellar OCD could return to their preinjury baseball ability and that 8 of the 11 lesions completely healed as seen radiographically11. Radiographic and magnetic resonance imaging (MRI) findings showed that BPG could secure the lesion to the osseous floor as a physiological scaffold. Fragment fixation with metal implants or biodegradable materials carries a risk of damaging cartilage surfaces, and autologous osteochondral grafting is too invasive for this early-stage lesion. BPG is indicated for ICRS OCD I or II lesions, especially with central positioning and/or occupying <75% of the size of the capitellum in the coronal plane11.

Recurrent Cubital Tunnel Syndrome Caused by Ganglion: A Report of Nine Cases.

BACKGROUND: Cubital tunnel syndrome (CuTS) is generally treated successfully by surgery and recurrent cases are rare. This study retrospectively investigated the clinical characteristics of recurrent CuTS caused by ganglion. METHODS: We evaluated nine patients who were surgically treated for recurrent CuTS caused by ganglion. Age distribution at recurrence ranged from 43 to 79 years. The initial surgery for CuTS had been performed using various methods. The asymptomatic period from initial surgery to recurrence ranged from 22 to 252 months. Clinical, diagnostic imaging, and operative findings during the second surgery were analyzed. All patients were treated by anterior subcutaneous ulnar nerve transposition with ganglion resection and later examined directly within a mean of 71 months after the second surgery. RESULTS: The interval from recurrence to consultation was shorter than two months for eight cases. Chief complaints included numbness with or without pain in the ring and little fingers in all patients and resting pain in the medial elbow in five patients. Elbow osteoarthritis was present in all cases. Although four of 10 ganglia were palpable, ultrasonography and magnetic resonance imaging could identify all ganglia preoperatively. The ulnar nerve typically had become entrapped by the ganglion posteriorly and by fascia, scar tissue, and/or muscle anteriorly. Chief complaints and ulnar nerve function were improved in all patients following revision surgery. CONCLUSIONS: The acute onset of numbness with or without intolerable pain in the ring and little fingers after a long-term remission period following initial surgery for CuTS in patients with elbow osteoarthritis appears to be the characteristic clinical profile of recurrent CuTS caused by ganglion. As ganglia are often not palpable, ultrasonography and magnetic resonance imaging are recommended for accurate diagnosis.

Physical interaction of junctophilin and the CaV1.1 C terminus is crucial for skeletal muscle contraction.

Close physical association of CaV1.1 L-type calcium channels (LTCCs) at the sarcolemmal junctional membrane (JM) with ryanodine receptors (RyRs) of the sarcoplasmic reticulum (SR) is crucial for excitation-contraction coupling (ECC) in skeletal muscle. However, the molecular mechanism underlying the JM targeting of LTCCs is unexplored. Junctophilin 1 (JP1) and JP2 stabilize the JM by bridging the sarcolemmal and SR membranes. Here, we examined the roles of JPs in localization and function of LTCCs. Knockdown of JP1 or JP2 in cultured myotubes inhibited LTCC clustering at the JM and suppressed evoked Ca2+ transients without disrupting JM structure. Coimmunoprecipitation and GST pull-down assays demonstrated that JPs physically interacted with 12-aa residues in the proximal C terminus of the CaV1.1. A JP1 mutant lacking the C terminus including the transmembrane domain (JP1ΔCT) interacted with the sarcolemmal/T-tubule membrane but not the SR membrane. Expression of this mutant in adult mouse muscles in vivo exerted a dominant-negative effect on endogenous JPs, impairing LTCC-RyR coupling at triads without disrupting JM morphology, and substantially reducing Ca2+ transients without affecting SR Ca2+ content. Moreover, the contractile force of the JP1ΔCT-expressed muscle was dramatically reduced compared with the control. Taken together, JPs recruit LTCCs to the JM through physical interaction and ensure robust ECC at triads in skeletal muscle.

Increase in phospholamban content in mouse skeletal muscle after denervation.

It is well-known that denervation of motor nerves induces atrophy and decreases contractile force of the skeletal muscle. However, it is not completely understood how denervation alters calcium handling in the skeletal muscle. We investigated the effect of denervation on the expression and function of proteins involved in calcium handling. Two weeks after denervation of the right sciatic nerve in mice, we observed a significant decrease in mass and cross-sectional area of the ipsilateral tibialis anterior (TA) and flexor digitorum brevis (FDB) muscles. Also, we observed a significant decrease in the specific tetanus contractile force in the ipsilateral TA muscle. Calcium imaging of the ipsilateral FDB showed that the peak twitch and tetanus calcium concentrations were significantly decreased due to a decrease in calcium content of the sarcoplasmic reticulum (SR). Denervation reduced the maximum rate of sarcoplasmic/endoplasmic calcium ATPase (SERCA) activity. Interestingly, the amount of phospholamban (PLN), but not its transcripts, was increased in the ipsilateral vs. contralateral side after denervation, suggesting that denervation impairs constitutive regulation of PLN. Immunohistochemical analysis revealed increased PLN in all major fiber types in TA with IIx fibers showing a threefold higher expression than the contralateral side. These results suggest that the abnormal increase in PLN in the ipsilateral fast-twitch fibers may be involved in decreased SERCA activity, SR calcium content, peak calcium transients, and contractile forces of denervated muscles.

Increased Serum 25(OH)D3 Levels in Post-Menopausal Japanese Women with Osteoporosis after 3-Year Bisphosphonate Treatment.

Osteoporosis is characterized by the systemic impairment of bone mass, strength, and microarchitecture, leading to an increased risk of fragility fracture. Bisphosphonates (BPs) are the first-line drugs for osteoporosis. Vitamin D is considered to be essential for osteoporotic treatment. However, long-term effects of BPs on the serum levels of 25-hydroxyvitamin D3 (25(OH)D3) are unknown. Accordingly, in this retrospective study, we collected clinical data of 41 post-menopausal Japanese women with osteoporosis treated with BP for over 3 years, without vitamin D supplementation. We measured lumbar and femoral neck bone mineral density (BMD) and serum levels of bone specific alkaline phosphatase (BAP) as a bone formation marker, and tartrate-resistant acid phosphatase (TRACP)-5b as a bone resorption marker, before and after the 3-year treatment. Serum 25(OH)D3, 1,25(OH)2D3, and whole parathyroid hormone (PTH) were also measured. Notably, no fracture occurred during the treatment. Compared with baseline values, 25(OH)D3 levels were significantly increased from 21.6 to 26.4 ng/mL (P = 0.006), despite no vitamin D supplementation. 1,25(OH)2D3 and whole PTH levels tended to be decreased from 62.6 to 57.8 pg/mL and 27.3 to 25.1 pg/mL, respectively. Both bone formation and resorption markers were significantly suppressed (P < 0.01). Both lumbar BMD (7.3% increase) and femoral neck BMD (4.1% increase) were significantly improved (P < 0.0001) after 3 years of the treatment. Thus, even without vitamin D supplementation, serum 25(OH)D3 levels were significantly increased after 3-year BP therapy. These results suggest that vitamin D supplementation might not be required in the long-term BP therapy for osteoporosis.

Myostatin promotes tenogenic differentiation of C2C12 myoblast cells through Smad3.

Myostatin, a member of the transforming growth factor-ß (TGF-ß) superfamily, is expressed in developing and adult skeletal muscle and negatively regulates skeletal muscle growth. Recently, myostatin has been found to be expressed in tendons and increases tendon fibroblast proliferation and the expression of tenocyte markers. C2C12 is a mouse myoblast cell line, which has the ability to transdifferentiate into osteoblast and adipocyte lineages. We hypothesized that myostatin is capable of inducing tenogenic differentiation of C2C12 cells. We found that the expression of scleraxis, a tendon progenitor cell marker, is much higher in C2C12 than in the multipotent mouse mesenchymal fibroblast cell line C3H10T1/2. In comparison with other growth factors, myostatin significantly up-regulated the expression of the tenogenic marker in C2C12 cells under serum-free culture conditions. Immunohistochemistry showed that myostatin inhibited myotube formation and promoted the formation of spindle-shaped cells expressing tenomodulin. We examined signaling pathways essential for tenogenic differentiation to clarify the mechanism of myostatin-induced differentiation of C2C12 into tenocytes. The expression of tenomodulin was significantly suppressed by treatment with the ALK inhibitor SB341542, in contrast to p38MAPK (SB203580) and MEK1 (PD98059) inhibitors. RNAi silencing of Smad3 significantly suppressed myostatin-induced tenomodulin expression. These results indicate that myostatin has a potential role in the induction of tenogenic differentiation of C2C12 cells, which have tendon progenitor cell characteristics, through activation of Smad3-mediated signaling.

Bony findings detected by MRI may reflect the pathophysiology of osteoarthritis with thumb carpometacarpal joint pain.

BACKGROUND: Osteoarthritis (OA) is the most common skeletal disease worldwide. Although thumb carpametacarpal joint (CMJ) OA is also frequently encountered, the etiologies remain largely unknown. METHOD: We analyzed 20 patients who had thumb CMJ OA with accompanying joint pain and categorized a total of 37 thumbs according to the Eaton and Littler staging system. RESULTS: In patients with advanced OA, bone alterations as detected by magnetic resonance imaging (MRI) were observed in almost all of the painful joints. The frequency of bone alterations in the thumb CMJ increased with OA severity. In contrast, MRI revealed no bone alterations in thumbs with no pain and less pain in bilateral thumb basal pain, even in radiographically advanced OA. CONCLUSIONS: While the incidence of bone cysts in the CMJ was higher with OA staging, OA severity had no apparent correlation with pain. Thus, it is possible that the cause of thumb CMJ pain in advanced OA is bone alterations.

Challenges of Transarticular Screw Fixation in Young Children: Report of Surgical Treatment of a 5-Year-Old Patient's Unstable Os-Odontoideum.

Surgical procedures for atlantoaxial (C1-C2) fusion in young children are relatively uncommon. The purpose of this study was to report on a surgical treatment for a case of atlantoaxial instability caused by os-odontoideum in association with quadriparesis and respiratory paralysis in a 5-year-old girl. We present the patient's history, physical examination, and radiographic findings, describe the surgical treatment and a five year follow-up, and provide a literature review. The instability was treated by halo immobilization, followed by C1-C2 transarticular screw fixation using a computed tomography-based navigation system. At the five year follow-up, the patient had made a complete recovery with solid union. The authors conclude that C1-2 transarticular screw fixation is technically possible as in a case of atlantoaxial instability in a five-year-old child.

Associations of self-reported height loss and kyphosis with vertebral fractures in Japanese women 60 years and older: a cross-sectional survey.

Some vertebral fractures come to clinical attention but most do not. This cross-sectional survey aimed to clarify the associations of self-reported height loss and kyphosis with vertebral fractures. We enrolled 407 women aged 60-92 years who visited our orthopaedic clinic between June and August 2014 in our study. Inclusion criteria were lateral radiography followed by completion of a structured questionnaire in this study. The primary outcome was vertebral fracture diagnosed on lateral radiography and graded using a semiquantitative grading method, from SQ0 (normal) to SQ3 (severe). Self-reported kyphosis was defined as none, mild to moderate, severe. Self-reported height loss was defined as <4 cm or ≥4 cm. Number of SQ1 fracture was associated only with kyphosis. Self-reported severe kyphosis was significantly associated with increased numbers of ≥SQ2 vertebral fractures (p = 0.007). Height loss ≥4 cm was significantly associated with increased ≥SQ2 grade fractures (p < 0.001). Odds ratios (ORs) for fractures associated with mild-to-moderate and severe kyphosis were 2.1 [95% confidence interval 1.4 to 3.3) and 4.2 (1.8 to 9.5), respectively. OR for fractures associated with height loss ≥4 cm was 2.3 (1.4 to 3.7). Self-reported kyphosis may be useful for identifying Japanese women aged ≥60 years who have undetected vertebral fractures.

Bone alterations are associated with ankle osteoarthritis joint pain.

The etiology of ankle osteoarthritis (OA) is largely unknown. We analyzed 24 ankle OA of 21 patients diagnosed by plain radiographs using magnetic resonance imaging (MRI). Ankle joint pain disappeared in 22 out of 24 joints by conservative treatment. MRI bone signal changes in and around the ankle joints were observed in 22 of 24 joints. Bone signal changes along the joint line were seen in 10 of 11 joints as a Kellgren-Lawrence (KL) grade of II to IV. Such signal changes were witnessed in only 4 of 13 joints with KL grade 0 or I. In the talocrural joint, bone alterations occurred in both tibia and talus bones through the joint line in cases of KL grade III or IV, while focal bone alterations were present in the talus only in KL grade I or II cases. Sixteen of 24 joints exhibited intraosseous bone signal changes, which tended to correspond to joint pain of any ankle OA stage. Our results suggest that bone alterations around the ankle joint might be one of the etiologies of OA and associated with ankle joint pain.

Monthly minodronate inhibits bone resorption to a greater extent than does monthly risedronate.

As a bisphosphonate, minodronate (MIN) is one of the strongest inhibitors of bone resorption. However, there have been no reports directly comparing the antiresorptive effects of monthly MIN with those of monthly risedronate (RIS). We enrolled 30 cases of osteoporosis (OP; 16 in the MIN group [mean age: 68.2 years] and 14 in the RIS group [mean age: 68.1 years]) to investigate the early effects of treatment by monthly MIN or RIS over a 4-month period using bone turnover marker values. Only female patients were enrolled to avoid gender bias. Urinary cross-linked N-telopeptide of type I collagen (NTX) before treatment and at 1, 2, and 4 months of therapy, as well as serum bone alkaline phosphatase and alkaline phosphatase before treatment and at 4 months afterwards, were evaluated. All bone turnover marker values were significantly decreased at 4 months in both groups. The changes in urinary NTX at the study end point for RIS and MIN were -30.1% and -63.1%, respectively. From 2 months of treatment, the antiresorptive effects on urinary NTX by MIN were significantly higher than those by RIS, indicating that MIN more immediately and strongly inhibited bone absorption. Thus, monthly MIN seems to suppress bone resorption faster and more strongly than RIS in OP treatment.

A case series of pregnancy- and lactation-associated osteoporosis and a review of the literature.

The syndrome of pregnancy- and lactation-associated osteoporosis is a rare disorder whose precise etiology and treatment are largely unknown. We herein report two such cases occurring in the early postpartum period that led to multiple fragility compression fractures. Combination therapy of vitamin D and vitamin K enabled a marked gradual increase in bone mineral density.

Risk Assessment of Tendon Attrition Following Treatment of Distal Radius Fractures With Volar Locking Plates Using Audible Crepitus and Placement of the Plate: A Prospective Clinical Cohort Study.

PURPOSE: To identify risk factors for tendon attrition after volar locking plate fixation of distal radius fractures. METHODS: We prospectively assessed attrition of the flexor pollicis longus tendon at volar plate removal in 127 hands in 126 patients. We also evaluated preoperative lateral wrist radiographs, sonographs, and crepitus with flexor pollicis longus tendon motion and compared the demographic and radiographic characteristics of patients with and without tendon attrition. Multivariate logistic regression analysis was employed to identify the factors independently associated with tendon attrition. RESULTS: We found 12 cases of tendon attrition (10%) and 1 that presented with tendon rupture in our cohort. Crepitus was recognized in 14 patients (11%): 6 cases (50%) were among the 12 hands in 12 patients with tendon attrition whereas 8 (7%) were detected in the remaining 114 hands in 113 patients. Logistic regression examination revealed that audible crepitus and volar placement of the plate in lateral radiographs were independent predictors of tendon attrition. CONCLUSIONS: Crepitus and volar placement of hardware in lateral radiographs were independent risk factors for flexor tendon attrition after volar plating for distal radius fracture. These results may facilitate surgical decisions regarding early plate removal to prevent possible tendon rupture. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic II.

Expression profiles of human CCN genes in patients with osteoarthritis or rheumatoid arthritis.

OBJECTIVE: Osteoarthritis (OA) and rheumatoid arthritis (RA) are widespread disabling joint disorders that are considered to be polygenic in nature. This study investigated the spatial expression patterns of all six known human CCN genes using end-stage OA and RA joint samples. DESIGN: We performed in situ hybridization and histological analysis to investigate the spatial expression patterns of human CCN genes using joint tissues obtained during total knee and hip joint replacement procedures on patients with advanced OA or RA. Normal joint tissues taken while performing bipolar hip replacement surgeries were used as controls. RESULTS: All CCN genes were expressed at higher levels in OA and RA synovial samples as compared with normal controls. Whereas CCN3 and CCN6 were undetectable in control, OA, and RA cartilage, CCN1, CCN2, CCN4, and CCN5 were expressed to a greater extent in OA and RA knee cartilage. CONCLUSIONS: Our results indicate an involvement of several CCN genes in the pathophysiology of OA and RA.

Percutaneous Transluminal Angioplasty for Axillary Artery Dissection After Open Reduction of Shoulder Fracture-Dislocation: A Case Report.

CASE: Injury of the axillary artery after shoulder-joint fracture or dislocation is uncommon. We describe the clinical outcome of an elderly patient with a dissecting aneurysm of the axillary artery following open reduction of a fracture-dislocation of the shoulder. The arterial dissection was successfully managed with percutaneous transluminal balloon angioplasty. CONCLUSION: This case report highlights the need for careful vascular examination of all elderly patients with a fracture or dislocation of the shoulder and the possible use of percutaneous transluminal angioplasty for the management of arterial dissection prior to proceeding with surgical exploration.