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At least 469 records · Page 26Linked to original sources
PubMed2003

Progressive collapse of transposed necrotic area after transtrochanteric rotational osteotomy for osteonecrosis of the femoral head induces osteoarthritic change. Mid-term results of transtrochanteric rotational osteotomy for osteonecrosis of the femoral head.

INTRODUCTION: Osteonecrosis of the femoral head is usually progressive, and once collapse of the femoral head develops, joint destruction almost invariably follows. Therefore, for partial osteonecrosis of the femoral head, various types of osteotomies have been developed in an attempt to save the femoral head and maintain the natural function of the hip joint. MATERIALS AND METHODS: We reviewed 25 hips in 21 patients for a mean follow-up period of 6.4 years after Sugioka's transtrochanteric anterior rotational osteotomy for osteonecrosis of the femoral head. RESULTS: The clinical results were excellent or good in 20 hips (80%), and radiological success was observed in 15 hips (60%) with an absence of both collapse of the newly established weight-bearing area of the femoral head and narrowing of the joint space. Progressive collapse of the transposed necrotic area was noted in 10 hips (40%), and of these 10 hips, narrowing of the joint space was observed in 7 (70%) at follow-up. A significant correlation was demonstrated between progressive collapse of the transposed necrotic area and narrowing of the joint space. Growth of an osteophyte of the femoral head was observed postoperatively in 16 hips (64%), particularly at anterior and lateral sites of the femoral head. CONCLUSIONS: Though collapse of a new weight-bearing area can be prevented, progressive collapse of the transposed necrotic area induces anterior joint instability, giving rise to osteoarthritic change. It is therefore concluded that prevention of the collapse of the transposed necrotic area is important for satisfactory long-term results.

Adult↗
PubMed1990

[Arthrosonography--a modern method for morphologic and functional joint evaluation in hemophilia].

The arthrosonography is a new depicting procedure for detection of destructing joint processes in haemophilia. A direct evaluation of the cartilage, of the border between cartilage and bone, of the synovial membrane with proliferative processes as well as the differentiation between soft-tissue bleeding and haemarthros are possible. An essential advantage is given by a combined morphological and functional joint evaluation. The diagnosis of joint instabilities can be recognized easier by sonography than by X-ray. Clinical findings are completed in an excellent manner and lesions of bone and cartilage are detected earlier by arthrosonography.

Adolescent↗
PubMed2002

Progressive surgical release of a posttraumatic stiff elbow. Technique and outcome after 2-18 years in 46 patients.

We treated 46 consecutive patients (47 elbows) suffering from posttraumatic contracture of the elbow joint with operative release. A lateral approach was used to perform a capsulectomy after release of the extensor muscles in 23 elbows. An additional medial approach was used to excise ulnar adhesions and perform a more extensive capsulectomy and an ulnar nerve neurolysis in 24 elbows. Postoperative rehabilitation consisted of immediate passive range-of-motion exercises. The results were assessed after average 10 (2-18) years. Before surgery, the mean active arc of motion was 45 (SD 36) degrees, which improved to 99 (SD 34) degrees after release. 7 patients had transient ulnar paresthesia, 4 recurrent stiffness, which did not become worse after surgery, 1 was reoperated on and 2 developed a postoperative infection, which responded to antibiotic treatment after a few months. No patient suffered from joint instability, or an increase in pain. 44 patients were satisfied with the result at the latest follow-up. We found similar improvement in both treatment groups.

Adolescent↗
PubMed1999

[Prophylactic surgery of the musculoskeletal system].

Prophylactic surgery on the musculoskeletal system has a wide range of indications, for example posttraumatic or non-traumatic malalignment of the lower extremities, joint instabilities or bony lesions with the risk of fracture and secondary malignant change. The goals of treatment include pain relief, improved function and redistribution of the physiological mechanical forces. Clinical experience over the past three decades has defined the current role of realignment of the lower limbs. Recent technological advances have further improved the surgical ability to assess and select patients who are candidates for realignment osteotomy or joint stabilization.

Humans↗
PubMed2005

An algorithm for estimation of shoulder muscle forces for clinical use.

BACKGROUND: The shoulder joint represents an indeterminate mechanical system, making it difficult to predict individual muscle forces required to equilibrate a given arbitrary external force. Although considerable work has been published on this matter, no model exhibits the adaptability required for the analysis involving different positions of the humerus and for any external load. An algorithm involving decision-making loops is developed to predict forces exerted by muscles that cross the shoulder joint in equilibrating a given external force acting in an arbitrary direction, with the humerus in any one of 12 selected positions. METHODS: Muscle lever arms and directions of action collected from a full-size epoxy model of the shoulder joint are used together with the external force as input. The algorithm selects an appropriate group of muscles and step by step attributes small force increments to withstand the external moment while aiming at minimising the forces involved. Each muscle force increment is stored after every loop and eventually summed up. Stability of the glenohumeral joint is the final determining factor. FINDINGS: Six worked-out examples show interesting features of probable muscular activity. Muscle segmentation is of paramount importance for spatial control. Although stability can be achieved by increasing the overall rotator cuff activity (co-contraction), this is rarely necessary. INTERPRETATION: The strategy of force sharing among the muscles opens up the possibility to examine the outcome of muscle deficiencies and to investigate causes of joint instability as encountered in clinical practice. Further validation of the model is still needed, but certain clinical observations can be explained.

Algorithms↗
PubMed1992

Proteoglycan synthesis and osteophyte formation in 'metabolically' and 'mechanically' induced murine degenerative joint disease: an in-vivo autoradiographic study.

We investigated the in-vivo proteoglycan synthesis in specific areas of murine knee joint articular cartilage after the induction of degenerative joint disease by means of 35S-sulphate autoradiography. Degenerative joint disease was induced either by direct interference with cartilage metabolism (papain and iodoacetate), or by the induction of joint instability (collagenase). Injection of iodoacetate and papain led to inhibition of proteoglycan synthesis mainly in the central parts of the patellae, patellaris femoris and the central part of the medial tibial plateau. Articular cartilage adjacent to the strongly inhibited areas frequently showed a significantly enhanced synthesis of proteoglycans. A strong inhibition of proteoglycan synthesis was observed in the central part of the medial plateau after collagenase injection while other cartilage sites and joint structures such as the capsule and ligaments were stimulated in their proteoglycan synthesis. This study shows that the localization of changes in cartilage metabolism in degenerative joint disease of the knee might be related to differences in the pathogenetic mechanism in different variants of this common joint disorder.

Animals↗
PubMedDate not supplied

[Secondary flattening of the acetabular roof in children].

The primary "idiopathic" shallow acetabuli within the classical complex of CDH are confronted with the rare secondary "symptomatic" dysplasias of the acetabular roof. They are encountered mainly in connection with neuromuscular diseases and bad static conditions about the hip-joint. Nine cases with secondary flattening of the acetabular roof of unknown aetiology are presented, probably partially due to CDH, in connection with slight cerebral disturbances, mental and physical retardation, hypotonia of the muscles, with general constitutional laxity of joints as well as with acquired local loosening of the joint capsule due to treatment, and with insufficiency of the hip-abductors. As with the classical CDH one may observe in those cases a lateralization of the femoral head in the absence of an interposition in the joint; increasing subluxations due to joint instability with increasing shallow acetabuli may start from infancy, many years prior to puberty. If conservative treatment--not prolonged--fails and the findings are deteriorating acetabuloplasty is indicated prior to intertrochanteric adduction osteotomy during the growth-period.

Acetabulum↗
PubMed1993

Mechanoreceptor endings in human cervical facet joints.

Normal cervical facet capsules, taken from three human subjects, were examined to determine the density and distribution of three types of mechanoreceptive nerve endings. Clearly identifiable mechanoreceptors were found in 80% of the specimens and were categorized according to the classification of Freeman and Wyke. Eleven Type I, twenty Type II, and five Type III receptors were identified, as well as a number of small, unencapsulated nerve endings. Type I receptors were small, globular structures measuring 25-50 microns in diameter. Type II receptors varied in size and contour, but were characterized by their oblong shape and broad, lamellar capsule. Type III receptors were relatively large, oblong structures with a thin, amorphous capsule, within which a reticular mesh-work of fine neurites was embedded. Free (nociceptive) nerve endings were found in sub-synovial, loose areolar, and dense capsular tissues. The presence of mechanoreceptive and nociceptive nerve endings demonstrates that cervical facet capsules are monitored by the central nervous system, and implies that neural input from the facets is important to the function of the cervical spine. Previous studies have suggested that protective muscular reflexes modulated by these types of mechanoreceptors are important in preventing joint instability and degeneration. The complex neural elements identified in this study may be damaged inadvertently when surgically exposing the cervical spine. Care should be taken, during posterior approaches, to avoid excessive stripping of the facets in portions of the spine not being fused.

Cervical Vertebrae↗
PubMed1996

[Shoulder problems in leisure athletes: physical examination, diagnosis and therapy. Sensible procedures in daily practice].

At first sight the anatomy of the shoulder may seem simple (see Fig. 1). However, for the physician treating a patient suffering from shoulder pain, the scapulo-thoracal interplay of 5 joints and 19 muscles, providing a wide and varied range of motion, may constitute an obstacle difficult to overcome. In the leisure athlete acute injuries must be distinguished from degenerative disease. Contact sports in particular tend to involve risks of falling on the shoulder, injuring the shoulder girdle or the elbow and wrist, sometimes with major consequences: complex fractures, dislocations, ligament and tendon lesions or joint instabilities. Thorough, rapid and cost-effective diagnostic evaluation of the athlete, involving clinical examination (function tests), radiographic imaging (shoulder a.p., y-view) and in selected cases ultrasonography (compared with the other side) may be necessary in starting early and effective therapy.

Acromioclavicular Joint↗
PubMed1992

[Extra-articular fractures near the knee and concomitant knee damage].

While the prognosis of intra-articular fractures of the knee joint is determined by the reconstruction of the articular surfaces, ligamentous damage and resulting joint instability is a main problem with extra-articular fractures neighbouring the knee. In a follow-up of 43 cases of A 1-3 fractures according to the AO/ASIF classification, 37.2% of the patients revealed concomitant ligamentous damage. Especially supracondylar femoral fractures and the avulsion fractures of the posterior cruciate and lateral collateral ligament are at higher risk.--Ligamentous ruptures accompanying avulsion fractures should be treated primarily according to the rules of knee joint surgery. In cases of supracondylar femoral fractures after open reduction and internal fixation the recovery of knee joint motion is more important than joint stability. Therefore ligamentous repair has to be performed secondarily if necessary.

Adolescent↗
PubMedDate not supplied

Fractures of the proximal interphalangeal joint.

Fractures of the proximal interphalangeal joint constitute a broad spectrum of injuries. An understanding of the anatomy, the potential for joint instability, and the treatment options is essential to management of these fractures. Commonly observed fracture patterns involve one or both condyles of the proximal phalanx or the base of the middle phalanx. Fractures of the middle phalanx may involve the palmar lip or the dorsal lip or may be a "pilon" type of injury involving both the palmar and the dorsal lip with extensive intra-articular comminution. Intra-articular injuries may lead to joint subluxation or dislocation and must be identified in a timely manner to limit loss of motion, degenerative changes, and impaired function. These injuries range from those requiring minimal intervention to obtain an excellent outcome to those that are challenging to the most experienced surgeon. The treatment options include extension-block splinting, percutaneous pinning, traction, external fixation, open reduction and internal fixation, and volar-plate arthroplasty. Prompt recognition of the complexity of the injury and appropriate management are essential for an optimal functional outcome.

Biomechanical Phenomena↗
PubMed2002

[Recurrent dislocation of the patella--arthroscopic therapy].

PURPOSE OF THE STUDY: The authors present results of the surgical treatment of the recurring patella dislocation. They use the surgical technique of medial percutaneous raphe by absorbable PDS suture and lateral release with arthroscopis assistance. MATERIAL: The operation was performed for recurring dislocation in 19 cases in 16 patients. Three patients underwent a surgery on both knees. The average age of patients was 22 years (range, 14-29 years). The average period after the surgery was 22 months (range, 12-45 months). Minimal number of dislocations prior to operation was 3, maximal more than 20. METHOD: The surgical technique consists in medial raphe by percutaneously inserted absorbable PDS suture with arthroscopic assistance and in performing a lateral release in the "closed manner" under the check of the arthroscope. After-care consists in the application of a rigid orthesis which is starting from the first postoperative day removed for physiotherapy by CPM. After two weeks a hinged orthesis is used with a gradual increase of the range of motion. After 6 weeks the patient starts full weightbearing without any fixation. The authors evaluated the results of the operation after Bentley. They also followed the duration of turniquet of the operated on limb, the duration of hospitalization and the period necessary for the achievement of the full range of motion. Radiograph was used for the determination of the shape of patella after Baumgartl and Wiberg, the angle of the femoral sulcus, the height of patella after the Insall-Salvati index and lateral shift of patella. Arthroscopic examination focused on the evaluation of the patellar and femoral chondromalacy and its classification after Outerbridge. Clinically, Q angle was measured, the axis of the limb, anxiosity test was made and the presence of crepitation was checked. RESULTS: Ninety per cent of the patients evaluated the condition after the surgery as very good or good, twice as poor. In one patient there occurred one recurrence of dislocation after the surgery. In the second patient after the surgery pain aggravated in connection with a severe degenerative damage of the femoropatellar joint. Neither avascular necrosis of the patella nor any more extensive bleeding was encountered. There was no infectious complication in the group of patients. Chondral lesion was recorded in 80% of patients. The degree of the damage increased with the number of dislocations. A frequent complication was a recurring knee effusion with the necessity of its evacuation. The relation between the number of dislocations and the final outcome of the surgery was proved. No patient with the number of dislocations 10 and more was evaluated as excellent. DISCUSSION: AS release and medial raphe is a surgical technique which brings very good and good results in a high number of patients. Independently performed raphe or release do not have comparable good results in the therapy of recurring dislocation. The authors' results do not differ from data in specialised literature. CONCLUSION: Arthroscopically performed lateral release and medial raphe by percutaneously inserted suture and with AS assistance has a number of unquestionable benefits. The performance is associated with only minimum complications. It reduces the duration of hospitalization, immobilization of the limb, duration of physiotherapy as well as the total duration of the incapacity to work. The cosmetic result is good. It is possible to operate on also on young patients prior to the final ossification in the area of the tibial tubercle. A prerequisite of a good result is an accurate performance of the operation and subsequent physical therapy. Contraindications include marked degenerative changes in the femoropatellar joint, instability of the knee, patella dislocation in TKR. Q angle exceeding 30 degrees and valgus deformity of the limb exceeding 15 degrees. A high number of dislocations and the resulting more severe damage to the cartilage reduce the potential for achieving excellent results.

Adolescent↗
PubMed1999

Animal models of arthritis in NOS2-deficient mice.

OBJECTIVE: To study the role of nitric oxide (NO) in cartilage destruction in murine models of arthritis and osteoarthritis. METHODS: Joint inflammation was induced in the knee joint by intraarticular injection of Zymosan. Osteoarthritis was induced by local injection of bacterial collagenase, causing joint instability. The effect of NO deficiency was studied by comparing the effects in normal mice and mice with genetically disrupted NOS2 (inducible NO synthase). Impact on articular cartilage was evaluated by histology and measurement of chondrocyte 35S-proteoglycan synthesis. RESULTS: NOS2 deficiency prevented chondrocyte proteoglycan synthesis inhibition in the arthritic cartilage and restored normal responsiveness to IGF-1. Net cartilage proteoglycan depletion was markedly reduced in the absence of NOS2, although inflammation was hardly affected. Osteoarthritic joint pathology was also significantly reduced, including diminished cartilage lesions and osteophyte formation. CONCLUSION: NO plays a major role in cartilage damage in both arthritic and osteoarthritic conditions.

Animals↗
PubMed2006

Endothelial dysfunction and decreased vascular responsiveness in the anterior cruciate ligament-deficient model of osteoarthritis.

Chronic inflammation associated with osteoarthritis (OA) may alter normal vascular responses and contribute to joint degradation. Vascular responses to vasoactive mediators were evaluated in the medial collateral ligament (MCL) of the anterior cruciate ligament (ACL)-deficient knee. Chronic joint instability and progressive OA were induced in rabbit knees by surgical transection of the ACL. Under halothane anesthesia, laser speckle perfusion imaging (LSPI) was used to measure MCL blood flow in unoperated control (n = 12) and 6-wk ACL-transected knees (n = 12). ACh, bradykinin, histamine, substance P (SP), and prostaglandin E(2) (PGE(2)) were applied to the MCL vasculature in topical boluses of 100 microl (dose range 10(-14) to 10(-8) mol). In normal joints, ACh, bradykinin, histamine, and PGE(2) evoked a dilatory response. Substance P caused a biphasic response that was dilatory from 10(-14) to 10(-11) mol and constricting at higher doses. In ACL-deficient knees, ACh, bradykinin, histamine, and SP decreased perfusion, whereas PGE(2) had a biphasic response that decreased perfusion at 10(-14) to 10(-11) mol and was dilatory at higher concentrations. Sodium nitroprusside increased perfusion in resting and phenylephrine-precontracted vessels with no significant differences between ACL-transected and control knees. Femoral artery occlusion and release increased perfusion by 74.3 +/- 11.1% in control knees but only by 25.8 +/- 4.4% in ACL-deficient knees. The altered responsiveness of the MCL vasculature to these inflammatory mediators may indicate endothelial dysfunction in the MCL, which may contribute to the progression and severity of OA and to the adaptation of the joint in an altered mechanical environment.

Animals↗
PubMed2002

Steady progression of osteoarthritic features in the canine groove model.

OBJECTIVE: Recently we described a canine model of osteoarthritis (OA), the groove model with features of OA at 10 weeks after induction, identical to those seen in the canine anterior cruciate ligament transection (ACLT) model. This new model depends on cartilage damage accompanied by transient intensified loading of the affected joint. The present study evaluates this groove model at 20 and 40 weeks after induction, to assess whether the osteoarthritic features progress in time. METHODS: Grooves were made in the femoral condyles of one knee without damaging the subchondral bone. After surgery the dogs were forced to load the experimental joint 3 days per week (4 hours/day) for 20 weeks by fixing the contralateral control limb to the trunk. After 20 weeks and 40 weeks (the last 20 weeks normal loading) joints were analysed for biochemical and histological features of OA. RESULTS: All biochemical cartilage parameters were indicative of OA and all these parameters suggested a slow progression of degeneration over time from 20 to 40 weeks after induction, statistically significant for synthesis and content of proteoglycans as well as Mankin grade. Synovial inflammation, which was mild, diminished slightly in time. CONCLUSION: The degenerative joint damage in the canine groove model is slowly progressive over time in the first year. The cartilage degeneration is induced by a one-time trauma and is not primarily mediated by synovial inflammation, which gives this model unique characteristics compared to presently available models for studying early osteoarthritic features in vivo. In the groove model the effect of treatment of cartilage damage is not counteracted by permanent joint instability or hampered by inflammation. Therefore, the model might be more sensitive to detect effects of therapy, aimed at cartilage protection and repair.

Animals↗
PubMed2004

First metatarsophalangeal joint arthrodesis.

First MTP joint arthrodesis continues to be a time-honored, effective, and valuable procedure as a primary or secondary surgery for various pathologies afflicting the first ray segment. Though commonly thought of as a salvage procedure, it has proven beneficial in the management of primary hallux limitus and rigidus, geriatric hallux valgus deformity, severe arthritis of any etiology, and conditions in which joint instability or deformity are not readily correctable by more traditional approaches. Since its initial description in the 1800s, the procedure has continued to be popular among orthopedic and podiatric surgeons. Success of the procedure is highly dependent on the position of fusion. Though surgeons are often fascinated and at times obsessed with a particular fixation technique, it cannot be over-emphasized that this takes a back seat to the importance of achieving proper position to meet the needs of an individual patient. Unlike joint resection or implant arthroplasty procedures, which commonly leave the hallux lacking stability and propulsion, first MPJ fusion has been shown to be effective during weight bearing and propulsion. The success enjoyed by the senior author continues to reinforce that motion is not necessary at the first MTP joint for good, pain-free function.

Arthrodesis↗
PubMed2006

[Arthroplasty of the rheumatoid hand. Pre- and postoperative imaging with special consideration of biomechanical and pathobiomechanical aspects and its radiological evaluation].

Radiology plays a key role when the indications for arthroplasties of the hand and finger joints are determined and for the postoperative follow-up. On the one hand, the degree of inflammatory changes in all affected compartments is to be evaluated and graded; on the other hand, conventional radiograms allow for a first assessment of possible joint instability and impaired biomechanics. Both aspects influence the choice of the proper surgical therapeutic strategy. Osteolysis, deformity, fracture, prosthesis loosening or failure, heterotopic ossification, and foreign body-associated formation of granulation tissue are complications which can be detected on follow-up radiographs early on.

Arthritis, Rheumatoid↗
PubMed1986

Ligamentous injuries of the hand in athletes.

Injuries to the small joints of the hand are prevalent in both professional and amateur athletes. The majority of these injuries result in partial tears of the capsular support structures and can be successfully treated by precise splinting followed by thorough rehabilitation. In contrast, optimal management of complex dislocations or complete ligament ruptures causing serious joint instability necessitates operative intervention to secure reduction and facilitate ligament healing. There is an enviable satisfaction in observing a recovered athlete perform to the limits of his or her abilities, unimpaired by any residual disability or deformity. This goal can only be achieved by the timely institution of skillful management.

Athletic Injuries↗