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PubMed2004

The prevalence of joint hypermobility among high school students.

OBJECTIVE: The aim of this study was to determine the prevalence of joint hypermobility among high school students and to define the characteristics of patients with joint hypermobility. METHODS: The students underwent complete history and physical examination. In order to designate marfanoid habitus, body weight, height, and span/height and upper/lower segment ratios were recorded. The degree of joint hypermobility was scored by the Beighton scoring system. The following features were also examined: arthralgia, myalgia, low back pain, sciatica, spinal deformities, temporomandibular joint pain and crepitus, effusion, swan neck deformity, arachnodactyly, joint dislocation, joint sprain, Raynaud's phenomenon, stria, varicose veins, abdominal and inguinal hernia, heart disease history, myopia, dropping eyelids, and antimongoloid slant. RESULTS: Eight hundred sixty-one students (433 females and 428 males) with a mean age of 15.4+/-1.1 years (range 13-19) were examined. Joint hypermobility was observed in 101 (11.7%) of the students. According to the Beighton scoring system, the majority of these (61.4%) were observed to score 4. Our results show that phenotype has no relation with joint mobility. Of the total number of students, there were 31 male (7.2%) and 70 female (16.2%) hypermobile subjects. The difference between sexes was highly significant (P=0.00005). Joint sprain was detected in 14 of hypermobile students (13.9%) and 50 of nonhypermobile students (6.6%). Its presence was the only significant parameter between hypermobile and nonhypermobile students (P=0.0094). CONCLUSIONS: Joint hypermobility was found in 11.7% of the students in our study, and the results are in harmony with the previous studies on Western populations. Although hypermobility does not seem to be very problematic in young people, as in our focus group, we believe that it is important for physicians to recognize this problem to ensure correct diagnosis and treatment, since it may lead to mimic rheumatic diseases in the future.

Adolescent↗
PubMed2004

Direct magnetic resonance arthrography.

Magnetic resonance (MR) arthrography has gained increasing popularity as a diagnostic tool in the assessment of intra-articular derangements. Its role has been studied extensively in the shoulder, but it also has been explored in the hip, elbow, knee, wrist and ankle. This article reviews the current role of direct MR arthrography in several major joints, with consideration of pertinent anatomy, techniques and applications.

Adult↗
PubMed2004

Cementless modular hip revision arthroplasty using the MRP Titan Revision Stem: outcome of 79 hips after an average of 4 years' follow-up.

INTRODUCTION: As primary total hip replacements (THRs) become more common in older patients and younger, physically active patients, the number of revision arthroplasties will also increase. Femoral bone loss, joint instability and possible infections are a challenge for a surgeon performing revision arthroplasty of the hip. The severe proximal femoral bone loss indicates the use of revision stems with a distal fixation. MATERIALS AND METHODS: In this study the clinical and radiological outcomes of 79 cementless stem revisions using the MRP Titan Revision Stem with an average follow-up time of 4 years were prospectively examined. RESULTS: The Harris Hip Score improved from preoperative 50.8+/-25.2 to postoperative 86.8+/-13.2. In all cases healing of bony defects could be found. For stem diameters larger than 17 mm, atrophy of the proximal femur and non-progressive radiolucent lines in zones 1 and 7 according to Gruen were detected. No disadvantages or complications of the Morse taper junctions were observed, and no osteolysis was detected in this region. Primary stable fixation was achieved in all but two cases. Three cases were revised again due to periprosthetic fracture (1) and persisting infection (2). CONCLUSION: Given the encouraging results with the MRP Titan Revision Stem, the principle of uncemented diaphyseal fixation appears to solve most of the technical problems in cases of significant bone loss and obviously offers good preconditions for bony restoration.

Aged↗
PubMed1993

Candida prosthetic arthritis: report of a case treated with fluconazole and review of the literature.

Prosthetic arthritis due to Candida species is uncommon, with only 15 cases reported in the literature. We recently cared for a human immunodeficiency virus-infected patient who developed Candida parapsilosis prosthetic arthritis unresponsive to resection arthroplasty, intravenous amphotericin B, and suppressive ketoconazole therapy. Treatment with fluconazole led to mycologic cure and symptom improvement, although he subsequently underwent above-the-knee amputation due to continued joint instability. Fluconazole may be useful follow-up therapy after a course of amphotericin B combined with resection arthroplasty or when removal of the prosthesis cannot be accomplished.

Adult↗
PubMed1996

In vitro laxity-testers for knee joints of mice.

The knee joints of mice can be used as a model for studying the effects of interventions on knee laxity. The goal of this study was to quantify knee joint laxity in vitro. Three devices were developed: a positioning- and cementing device, an anterior-posterior (AP) laxity tester and a varus-valgus (VV) laxity tester. The positioning and cementing device was used to position the joint in a reproducible way and to attach clamping pins to the proximal femur and distal tibia using PM MA. The clamping pins were used to fix the joint to the AP- and VV-testers. In both testers the load was applied by means of a spindle-actuated spring while load and displacements were measured simultaneously. The load--displacement data were used to calculate displacement and compliance parameters. The performance of the testers was evaluated by testing 5 normal knee joints of 5 mice. Total AP-translation at + or - 0.8 N was 0.43 (+ or - 0.16 S.D.) mm with compliances of 0.14 (+ or - 0.05 S.D.) mm N(1) and 0.12 ( + or - 10.05 S.D.) mm N(-1) at 0.8 N posterior and anterior force, respectively. Total VV-rotation at + or - 4 Nmm was 17.2 (+ or - 2.6 S.D.) degrees with compliances of 0.9 degrees Nmm(-1) (+ or - 0.2 degrees Nmm(-1) S.D.) and 1.0 Nmm(-1) (+ or - 0.4 degrees Nmm(-1) S.D.) at 4 Nmm valgus and varus moment, respectively. The contributions of the deformations of the bones and the fixtures to the rotations were negligible in the VV-test. In the AP-test they account for approximately 0.07 ( + or - 0.03 S.D.)mm of the total AP-translation. This will not affect the utilization of the device for comparative analysis. It is concluded that in in vitro evaluation of AP- and VV-laxity in knees of mice is feasible with sufficient accuracy for evaluation of changes after ligament damage.

Animals↗
PubMed1990

A critical analysis of Swanson ulnar head replacement arthroplasty: rheumatoid versus nonrheumatoid.

Clinical and radiographic assessment of the results of 40 Swanson silicone ulnar head prosthesis implants in three different patient groups is presented. Twenty-eight were done for treatment of rheumatoid arthritis, eight for ulnoradial impingement after the Darrach procedure, and four for ulnocarpal impingement resulting from malunited Colles' fractures. Patients were reviewed 12 to 48 months after operation (mean, 29 months). Seventy-eight percent of patients reported relief of pain and improved function. Radiologic examination showed that all patients exhibited resorption of the distal ulna (mean 4.4 mm) and that resorption was worst in the group with rheumatoid arthritis. Bone resorption about the implant predisposed the cap to both side-to-side tilt and pistoning of the prosthesis on supination and pronation. There was a 10% revision rate because of silicone synovitis. Although clinical results remain satisfactory for patients with rheumatoid arthritis and ulnocarpal impingement, the radiologic results suggest that Swanson ulnar head replacement should be restricted to elderly patients with rheumatoid arthritis.

Age Factors↗
PubMed1994

Thumb duplication, 66 years' experience--a review of surgical complications.

Fifty-four supernumerary thumbs excisions were followed for an average of 9 years for results of their surgical management, which consisted of simple excision (16 patients), reconstructive procedures (33 patients), or central wedge resections (5 patients). Half of all simple excisions and reconstructive procedures gave unacceptable results, most were salvaged. These were primarily joint deviations, joint instabilities, and bony prominences. All of our central wedge resections gave unacceptable results that were not salvageable--short, stiff, fat thumbs with nail deformities. We feel this procedure should probably be reserved for cases where both digits of the supernumerary thumbs are severely hypoplastic.

Adolescent↗
PubMed2005

Ulnar collateral ligament of the elbow.

Recent advances in the diagnosis and treatment of the overhead athlete's elbow has led the medical community to understand that the ulnar collateral ligament (UCL) of the elbow is more commonly injured than originally thought. Injury can result in secondary symptoms and problems in other regions of the elbow. Sports requiring an overhead motion, such as throwing a ball, hitting a ball overhead, or serving a tennis ball, imparts a valgus stress on the elbow that is resisted by the UCL. Throwing sidearm or hitting a forehand in tennis, squash, or racquetball may also impart a valgus stress to the elbow. Repeated or excessive valgus stress places a force on the UCL that may result in injury to the ligament. Injury to the UCL may result in problems in other areas of the elbow, including the ulnar nerve, the flexor-pronator musculotendinous unit, the radiocapitellar joint and the posterior compartment of the elbow, in addition to being a cause of loose bodies within the elbow. This article reviews the anatomy, biomechanics, and pathophysiology of injury to the UCL and injuries to the other structures that result from UCL injury. Also reviewed are patient history, examination techniques, tests that help confirm the diagnosis of UCL injury, and treatment of the injured UCL.

Arthroscopy↗
PubMed2004

Radiofrequency probe treatment for subfailure ligament injury: a biomechanical study of rabbit ACL.

OBJECTIVE: Utilizing a rabbit anterior cruciate ligament model of ligamentous subfailure injury, biomechanical properties of injured ligament treated with radiofrequency energy were evaluated. It was hypothesized that an injured ligament treated with radiofrequency probe would demonstrate restoration of biomechanical properties lost through injury. BACKGROUND: Radiofrequency probe, thermal treatment has been utilized in the clinical setting to address joint instability caused by ligamentous laxity from injury or repetitive microtrauma. The biomechanical effects of radiofrequency probe thermal treatment on injured ligamentous tissues have not been studied in the laboratory. DESIGN: Three groups of specimens: Control, Sham, and Treatment, 10 each, were tested under identical conditions. METHODS: Viscoelastic behavior was analyzed using a relaxation test (6% strain, up to 180 s) performed before injury, after injury, and after injury plus sham or injury plus radiofrequency probe treatment. RESULTS: After injury the normalized forces in the relaxation test decreased by approximately 50%. The post-treatment relaxation test revealed significant ( P < 0.01 ) restoration of the average relaxation force in the Treatment group to that of the Control group (0.79, SD 0.11 vs. 0.80, SD 0.10). Both of these groups were significantly different from the Sham group (0.44, SD 0.11). Additionally, stretch-to-failure test showed partial restoration of the toe region of the load-deformation curve by the radiofrequency treatment. CONCLUSIONS: The radiofrequency probe treatment is shown to be an effective mechanism for restoring initial ligament tensile stiffness and viscoelastic characteristics lost by the subfailure injury in vitro.

Animals↗
PubMed2004

A biomechanical model of the effect of subtalar arthroereisis on the adult flexible flat foot.

OBJECTIVE: The hypothesis tested was that the increased load on the medial arch in the adult flat foot can be reduced through a 6 mm subtalar arthroereisis. DESIGN: A three-dimensional multisegment biomechanical model was used in conjunction with experimental data and data from the literature. BACKGROUND: Biomechanical models have been used to study the plantar fascia, medial arch height, subtalar motion, medial displacement calcaneal osteotomy and distribution of forces in the foot. METHODS: Responses of a normal foot, a flat foot, and a flat foot with a subtalar arthroereisis to an applied load of 683 N were analyzed and the distribution of support among the metatarsal heads and the moment about various joints were computed. RESULTS: The flattened foot results in an increase in the load on the head of the first metatarsal from 10% to 24% of the body weight, and an increase in the moment about the talo-navicular joint from 3.4 to 11.9 Nm. Insertion of a 6 mm cylinder into the sinus tarsi, subtalar arthroereisis, results in a shift of the load back toward the lateral column, decreasing the load on the first metatarsal to 6% of the body weight and decreasing the moment about the talo-navicular joint to 6.0 Nm. CONCLUSIONS: Our analysis indicates that a 6 mm subtalar arthroereisis in an adult flat foot model decreases the load on the medial arch.

Adult↗
PubMed2006

Biomechanical performance of the new BeadEx implant in the treatment of osteoporotic vertebral body compression fractures: restoration and maintenance of height and stability.

BACKGROUND: Vertebral compression fractures are counted among the most common complications of osteoporosis. For treatment, a new, alternative implant has been developed (BeadEx, Expandis, Hof HaCarmel, Israel). The aim of the present in vitro study was to evaluate whether this implant is able to restore the initial height and three-dimensional stability after fracture and whether it is able to maintain this height and stability during complex cyclic loading. METHODS: The BeadEx implant consists of small titanium rolls, which are pressed into the vertebral body through specially designed, hollow pedicle screws. The height and the three-dimensional flexibility of 18 bisegmental spine specimens (nine T12-L2, nine L3-L5) was measured, first, before and after creating a wedge compression fracture at the middle vertebral body (L1 resp. L4), second, after treatment of the fracture, and, third, during and after complex cyclic loading. The fractures were treated either with BeadEx plus internal fixator, BeadEx plus bone cement or vertebroplasty for comparison. FINDINGS: The height before fracture could almost be restored by BeadEx plus bone cement but not by BeadEx plus fixator and vertebroplasty. The total height loss after cyclic loading was smallest with BeadEx plus bone cement (in median -4.7mm with respect to the intact specimens) but -6.2mm with BeadEx plus fixator and -7.8mm with vertebroplasty. The three-dimensional stability of the specimens was clearly higher if treated with BeadEx plus fixator than with BeadEx plus bone cement or vertebroplasty. INTERPRETATION: From a biomechanical point of view, BeadEx plus bone cement can be recommended as an alternative to vertebroplasty in the treatment of osteoporotic vertebral body fractures. BeadEx plus fixator can be recommended if additional stability is needed.

Biomechanical Phenomena↗
PubMed2006

The role of hip arthroscopy in the athletic hip.

Hip joint problems in the athlete can be disabling, yet remain elusive to investigation. The arthroscope has proved essential in both the detection and treatment of many of these disorders. Less invasive methods with quicker return to safe competition has been a sine qua non of sports medicine. The incentive to return motivated athletes to a sport has proven fertile ground for advancement of arthroscopic techniques. This has been especially exemplified in the rapidly evolving field of hip arthroscopy, and has allowed these methodologies to find application in the management of patients of all levels of activity. As has been stated, the athletic field of competition represents one of the most fertile clinical laboratories in the world.

Adolescent↗
PubMed2005

Orthopedic problems in geriatric dogs and cats.

Senior dogs and cats with orthopedic injuries and diseases often require a treatment plan that differs from that of younger patients. Injured bone and soft tissues tend to heal more slowly in the geriatric patient. The older animal is likely to have a less competent immune system and may have compromised metabolic and endocrine function. Pre-existing musculoskeletal problems may make ambulation difficult for an animal convalescing from a new orthopedic problem. Special attention is often needed when treating these patients for fractures, joint instability, infection, and neoplasia. In general, issues that should be addressed in the geriatric patient include reducing intraoperative and anesthesia time, enhancing bone and soft tissue healing, return to early function, control of postoperative pain, physical therapy, and proper nutrition.

Aging↗
PubMed2005

Traumatic luxations of the appendicular skeleton.

Traumatic luxation of joints of the appendicular skeleton is common.Timely and accurate identification of the luxation is essential to restoring normal function. Physical examination and radiographic assessment are commonly utilized for accurate identification and categorization. Conservative and surgical techniques are employed for treatment of luxations solely and in combination. Selection of appropriate reparative techniques is dependent on the joint injured as well as on other joint- and injury-specific factors.

Animals↗
PubMed2006

In vivo glenohumeral contact forces--measurements in the first patient 7 months postoperatively.

Knowledge of forces in the glenohumeral joint is essential for understanding normal and pathologic shoulder function. It forms the basis for performing fracture treatment or joint replacement surgery, for optimizing implant design and fixation and for improving and verifying analytical biomechanical models of the shoulder. An instrumented shoulder implant with telemetric data transmission was developed to measure six components of joint contact forces and moments. A patient with humeral head arthrosis achieved good joint function after its implantation. During the first 7 postoperative months, the contact force remained below 100% BW (percent body weight) for most activities of daily living. It ranged up to 130% BW for arm positions close to the limits of motion or when acting against external resistance. When the patient tried to turn a blocked steering wheel with maximum effort, the force rose to about 150% BW, the highest level observed thus far. Of great interest were the force directions relative to the humerus, especially those in the sagittal plane, which were not greatly influenced by the type of exercise, the arm position or the external resistance. The moments due to friction in the joint reached 5.2 Nm. The friction-induced shift of contact forces relative to the implant head centre ranged up to 6.3mm. These first worldwide in vivo measurements of glenohumeral contact forces are being continued in more patients and for longer postoperative times.

Follow-Up Studies↗
PubMed2005

Results from a degradable TMC joint Spacer (Artelon) compared with tendon arthroplasty.

PURPOSE: A new spacer for the trapeziometacarpal joint (TMC) based on a biological and tissue-preserving concept for the treatment of TMC osteoarthritis (OA) has been evaluated. The purpose was to combine a spacing effect with stabilization of the TMC joint. METHODS: Artelon (Artimplant AB, Sweden) TMC Spacer is synthesized of a degradable polyurethaneurea (Artelon), which has been shown to be biocompatible over time and currently is used in ligament augmentation procedures. Fibers of the polymer were woven into a T-shaped device in which the vertical portion separates the bone edges of the TMC joint and the horizontal portion stabilizes the joint. Fifteen patients with disabling pain and isolated TMC OA were included in the study. Ten patients received the spacer device and the remaining 5 (control group) were treated with a trapezium resection arthroplasty with abductor pollicis longus (APL) stabilization. The median ages of the 2 groups were 60 and 59 years, respectively. Pain, strength, stability, and range of motion were measured before and after surgery. Radiographic examination was performed in all patients before and after surgery. At follow-up evaluation 3 years after surgery an unbiased observer evaluated all patients. Biopsy specimens were obtained from 1 patient 6 months after surgery. RESULTS: All patients were stable clinically without signs of synovitis. In both groups all patients were pain free. The median values for both key pinch and tripod pinch increased compared with before surgery in the spacer group but not in the APL group. The biopsy examinations showed incorporation of the device in the surface of the adjacent bone and the surrounding connective tissue. No signs of foreign-body reaction were seen. CONCLUSIONS: This study showed significantly better pinch strength after Artelon TMC Spacer implantation into the TMC joint compared with APL arthroplasty.

Absorbable Implants↗