Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Joint Instability”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 433 records · Page 24Linked to original sources
PubMed2004

Operative treatment for degenerative lumbar spinal canal stenosis.

The authors have made a retrospective study of a cohort of patients who underwent surgery for spinal stenosis. A total of 85 patients were surgically treated for spinal stenosis between 1993 and 1997, and 79 patients were available for re-evaluation. The average time of follow-up was 79 months. Twenty patients with monosegmental stenosis underwent fenestration and undercutting, 16 patients had a hemilaminectomy or laminectomy and 43 patients had an instrumented fusion after decompression. The severity of the clinical complaints, the degree of stenosis and the extent of the instability determined the method of operation used. Results were more variable when extensive decompression (hemilaminectomy or more) was needed and segmental stability was reduced by resection of large portions of the facet joints. Instability clearly worsened the results. The overall results clearly show that limited decompression is an ideal operative method, provided the indication is correct. Fusion cannot be avoided if segmental instability is present. This retrospective study shows that satisfactory long-term results can be achieved in lumbar spinal stenosis with surgery adapted to the degree of instability and the degree of stenosis.

Adult↗
PubMed2006

Why lateral meniscectomy is more dangerous than medial meniscectomy. A finite element study.

Total meniscectomies are commonly thought to cause progressive degenerative arthrosis pathology in articular cartilage in a period of a few years because of alteration of the biomechanical environment including increased joint instability. This concern has lead to a preference for partial meniscectomies, although lateral partial meniscectomies sometimes lead to catastrophic results. We performed a three-dimensional finite element model of the human tibiofemoral joint to examine the effect of lateral meniscectomy on knee biomechanics. The results were compared to those from modeling a medial meniscectomy. Under axial femoral compressive loads, the peak contact stress and maximum shear stress in the articular cartilage increased 200% more after a lateral than a medial meniscectomy. These increased stresses could partly explain the higher cartilage degeneration observed after a lateral meniscectomy.

Adult↗
PubMed2005

Fibroblast growth factor-18 stimulates chondrogenesis and cartilage repair in a rat model of injury-induced osteoarthritis.

OBJECTIVE: Osteoarthritis (OA) is the most common form of arthritis and a primary cause of disability, however, there are no treatments that can slow disease progression or repair damaged joint cartilage. Fibroblast growth factor-18 (FGF18) has been reported to have significant anabolic effects on cartilage. We therefore examined its effects on repair of cartilage damage in a rat meniscal tear model of OA. DESIGN: Surgical damage to the meniscus in rats leads to joint instability and significant damage to the articular cartilage at 3 weeks post-surgery. At this time, animals received bi-weekly intra-articular injections of FGF18 for 3 weeks, and the knee joints were then harvested for histologic examination. RESULTS: FGF18-induced dose-dependent increases in cartilage thickness of the tibial plateau, due to new cartilage formation at the articular surface and the joint periphery. The generation of new cartilage resulted in significant reductions in cartilage degeneration scores. The highest dose of FGF18 also induced an increase in chondrophyte size and increased remodeling of the subchondral bone. CONCLUSIONS: The results of this study demonstrate that FGF18 can stimulate repair of damaged cartilage in a setting of rapidly progressive OA in rats.

Animals↗
PubMed1996

[Meniscus lesions after isolated anterior cruciate ligament rupture].

In this retrospective study the meniscal status of 34 patients with untreated complete anterior cruciate ligament (ACL) tears is reported. The anterior cruciate ligament injury was initially documented by examination under anesthesia and arthroscopy. Treatment in all cases consisted of a standard protocol of early rehabilitation and bracing. The mean follow-up was 7.3 years. Twenty-two (65%) patients showed signs of meniscal pathology at an average of 2.5 years after the ACL injury during the follow-up period. Rearthroscopy was performed and showed a higher incidence of medial meniscus tears (53%) than lesions of the lateral meniscus (41%). The most common tear of the medial meniscus was the bucket-handle type, followed by the flap tear and the single longitudinal split of the posterior horn. Secondary reconstruction of the ACL was necessary in 18 patients (82%) complaining of symptoms indicative of permanent anterior instability of the knee. The remaining 4 patients had rearthroscopy 3.5 years after the ACL injury and a partial meniscectomy and ACL reconstruction was performed. 12 patients (35%) had no symptoms or signs of joint instability or meniscal pathology during the follow-up period, but discontinued their sporting activities. This study indicates the increasing incidence of meniscal tears during ACL insufficiency. We recommend that patients with ruptures of the anterior cruciate ligament should be investigated for meniscal tears and that early ligament reconstruction of the knee and meniscal repair or partial meniscectomy should be considered simultaneously.

Adolescent↗
PubMed1982

[Combined malleolar lesion in the growing skeleton].

Some examples are given in order to describe the combined lesion of the ankle joint in the growing skeleton after a supination trauma. This lesion in the growing skeleton is similar to the basic type A of luxation fractures according to Weber[4]: lateral ligament rupture or lysis of the fibular zone of bone growth, respectively, combined with fracture of the medial malleolus and involvement of the tibial zone of bone growth. In some cases, anteroposterior radiographs are necessary in order to establish a complete diagnosis. The pictures should always be compared with those of the uninjured side. Skeletal dysplasia as well as joint instability can be avoided by a differentiated therapy depending on the initial findings.

Adolescent↗
PubMed1996

Recurrent dislocation of the pisiform bone.

A 17-year-old man had chronic pain and recurrent radial dislocation of the pisiform bone following a fall on his outstretched arm. The bone was excised, along with a 3 x 4-mm osteocartilaginous fragment from the distal triquetrum. Pisotriquetral joint instability should be considered in the differential diagnosis of palmar-ulnar wrist pain.

Adolescent↗
PubMed1995

Ligamentous and tendinous support of the pisiform: anatomic and biomechanical study.

Twenty-five formalin-preserved cadaveric wrists were dissected and the relationship of the pisotriquetral joint (PTJ) and its surrounding soft tissue structures were defined. An additional 4 fresh frozen wrists were examined in longitudinal and transverse sections. These anatomical studies showed the extensor retinaculum to have a complex insertion into the pisiform, flexor carpi ulnaris, fifth metacarpal, pisometacarpal ligament, and the abductor digiti minimi muscle. A capsuloligamentous structure on the medial aspect of the pisotriquetral joint was also identified. Biomechanical testing was performed on 12 fresh cadaver wrists and the results were compared to the anatomical findings to determine the contribution of surrounding soft tissue structures to pisotriquetral joint stability. Mechanical testing showed the soft tissues around the pisotriquetral joint to be strongest proximally and distally and weakest medially. Transection of the transverse carpal ligament resulted in increased lateral motion of the pisiform, but there was no significant decrease in stiffness. This study provides insight into the etiology of pisotriquetral joint instability and dysfunction.

Biomechanical Phenomena↗
PubMed2006

Degenerative and post-traumatic arthritis affecting the carpometacarpal joints of the fingers.

Symptomatic post-traumatic arthritis affecting the finger CMC joints is less common than might otherwise be expected based on the frequency of injury, especially to the fifth CMC joint. For the fifth CMC joint, the shallow concavoconvex articulation combined with the typical fracture location may provide a protective effect. Non-operative measures are typically successful, except in cases of missed fracture/dislocations and symptomatic joint instability. In these instances, re-construction emphasizes stability first, with an eye toward mobility for the ulnar column. It is common to detect a bony prominence in the region of the dorsal second and third CMC joints during examination of the hand. In most instances, the projection is asymptomatic and likely represents an os styloideum [18]. When painful and unresponsive to nonoperative treatments, this carpometacarpal boss can be excised surgically.

Carpal Joints↗
PubMed2006

Controlled, clinical trial assessing saphenous, tibial and common peroneal nerve blocks for the control of perioperative pain following femoro-tibial joint surgery in the nonchondrodystrophoid dog.

OBJECTIVE: To determine whether bupivacaine peripheral nerve block of the saphenous, tibial and common peroneal nerves proximal to the femoro-tibial joint reduces peri-operative pain following extracapsular surgical stabilization of cranial cruciate ligament rupture in the nonchondrodystrophoid dog. ANIMALS: Forty-one dogs with naturally acquired femoro-tibial joint instability. Study design Randomized, controlled, clinical trial. METHODS: Dogs diagnosed with suspected cranial cruciate ligament injury based on physical and radiographic evidence were randomly assigned to treatment (bupivacaine) or control (saline) nerve blocks before femoro-tibial joint surgery. Pain scores, skin sensation, pain threshold to incisional pressure, time to first systemic 'rescue' opioid analgesic and total analgesic dose were evaluated for 24 hours. p < 0.05 was considered significant. RESULTS: Treatment dogs had a significantly longer period of cutaneous desensitization than control dogs. There were no significant differences between treatment and control groups for pain score, pain threshold to incisional pressure, or time to first-rescue analgesic. The treatment group received significantly more supplemental analgesics than the control group. CONCLUSIONS: These peripheral nerve blocks were easy to perform and resulted in significant desensitization of the associated nerve autonomous zones, but did not improve post-operative analgesia. CLINICAL RELEVANCE: Clinical benefit was not detected when using this technique for peri-operative pain management following extracapsular cranial cruciate ligament surgical stabilization.

Anesthetics, Local↗
PubMed1995

Ligamentous and tendinous support of the pisiform, anatomic and biomechanical study.

Twenty-five formalin preserved cadaveric wrists were dissected and the relationship of the piso-triquetral joint and its surrounding soft tissue structures were defined. An additional 4 fresh frozen wrists were examined in longitudinal and transverse sections. These anatomical studies showed the extensor retinaculum to have a complex insertion into the pisiform, flexor carpi ulnaris, fifth metacarpal, piso-metacarpal ligament, and the abductor digit minimi muscle. A capsulo-ligamentous structure on the medial aspect of the piso-triquetral joint was also identified. Bio-mechanical testing was performed on 12 fresh cadaver wrists and the results were compared to the anatomical findings to determine the contribution of surrounding soft tissue structures to piso-triquetral joint stability. Mechanical testing showed the soft tissues around the piso-triquetral joint to be strongest proximally and distally and weakest medially. Transection of the transverse carpal ligament resulted in increased lateral motion of the pisiform, but there was no significant decrease in stiffness. This study provides insight into the etiology of piso-triquetral joint instability and dysfunction.

Biomechanical Phenomena↗
PubMed1988

Distal avulsion of the palmar plate of the interphalangeal joint of the thumb.

A 63-year-old woman was unable to actively flex the interphalangeal joint of her right thumb after a hyperextension injury. Surgical exploration revealed an avulsion of the distal insertion of the palmar plate, allowing the bulk of the plate to block the joint during attempted active flexion. Resection of the palmar plate restored active flexion and caused no joint instability. We do not believe this lesion, which resulted in this disability, has been previously described.

Cumulative Trauma Disorders↗
PubMed1997

Mechanical behavior and biochemical composition of canine knee cartilage following periods of joint disuse and disuse with remobilization.

The mechanical behavior and biochemical composition of articular cartilage were studied in an experimental model of joint disuse, in which the canine knee was immobilized in a sling at 90 degrees of flexion. Articular cartilage from the surface zone of the femur was tested in an isometric tensile test and full-thickness cartilage on the tibial plateau was tested in a compressive indentation test. Water, proteoglycan and collagen contents were measured in site-matched samples. Site-specific increases in the tensile moduli (approximately 88% above control values in distal femoral groove) were observed in cartilage after 8 weeks of joint disuse, and after 3 weeks of remobilization following either 4 (approximately 140%, distal and proximal femoral groove) or 8 weeks (approximately 140%, distal femoral groove) of joint disuse. In contrast, the compressive properties of cartilage determined in the indentation test exhibited no change from control values with joint disuse or disuse followed by remobilization. Water contents increased at some sites on the tibia after 8 weeks of joint disuse (approximately 6% of tissue wet weight, posterior site), but not in the surface zone tissue of the femur. Proteoglycan/collagen and cartilage thickness were not found to change with disuse or disuse followed by remobilization. Reduced values for the ratio of proteoglycan:water were observed in the surface zone tissue of the femur (approximately 23%, distal femoral groove) and in the full-thickness tissue of the tibia (approximately 21%, anterior and posterior sites) after periods of joint disuse. In this study, the measured material properties suggest that the articular surface remains intact following periods of disuse or disuse with remobilization. This finding suggests one important difference between this model of joint disuse and other experimental models in which cartilage changes are both progressive and degenerative, such as surgically-induced joint instability.

Animals↗
PubMed1992

Magnetic resonance imaging of the wrist.

Magnetic resonance (MR) imaging has developed rapidly as a diagnostic tool in the evaluation of the wrist. In this article, the authors review simple high-resolution technique and appropriate surface coils to aid in wrist evaluation. Evaluation of the wrist is facilitated by an understanding of the anatomy of the carpal ligaments, the triangular fibrocartilage, and the carpal tunnel, and the anatomic features of the distal radioulnar joint. Triangular fibrocartilage tears, which represent an important cause of ulnar wrist pain, are well evaluated on MR. These appear as a linear band of increased signal on the short repetition time/echo time (TR/TE), proton density weighted spin echo, or gradient echo images. True tears should be differentiated from degenerative changes, which do not demonstrate increase in signal on T2 or T2* weighted images. With good technique, accuracies approaching 90% have been reported. MR is also useful in evaluating injuries of the interosseous ligaments and volar and dorsal radiocarpal ligaments and distal radioulnar joint instability. MR also has a role in evaluating the carpal tunnel syndrome. This is especially true with patients for whom symptoms suggest the diagnosis of carpal tunnel syndrome but for whom few objective findings exist. Findings suggestive of carpal tunnel syndrome include diffuse swelling of the median nerve, flattening of the median nerve at the level of the hamate, and increased signal of the median nerve on the long TR/TE images. MR is also indicated in avascular necrosis of the carpal bones and occult carpal fractures. MR is useful in evaluating bone tumors, particularly with regard to their extent. With the advent of more rapid scanning techniques, kinematic studies are feasible. For these, fast gradient echo techniques are employed and serial images are acquired during radial and ulnar deviation. These images may be helpful in observing integrity of intercarpal ligaments and evaluating dynamic instability. With proper attention to technique, and an understanding of wrist pathophysiology, MR is a valuable diagnostic tool.

Cartilage, Articular↗
PubMed2002

Posterolateral aspect and stability of the knee joint. II. Posterolateral instability and effect of isolated and combined posterolateral reconstruction on knee stability: a biomechanical study.

This study evaluated the correlation between the number of transected posterolateral structures (PLS) and the grade of posterolateral rotational instability, determined the effect of the popliteus muscle-tendon unit on the tibial rotation, and examined the effect of an isolated posterior cruciate ligament (PCL) and combined PCL-PLS reconstruction on knee stability. Sectioning the popliteofibular and lateral collateral ligaments both caused an increase in tibial external rotation. Cutting the PT resulted in a statistically highly significant excessive external rotation and externally shifted neutral position of the tibia over the full range of motion. Tensioning the popliteus muscle-tendon unit led to a statistically highly significant internally shifted neutral tibial rotation and a decreased internal and an increased external rotation without affecting the total rotational arcs. The isolated PCL reconstruction did not affect the external rotation, whereas the combined PCL-PLS reconstruction reset the knee to nearly physiological laxity patterns.

Adult↗
PubMedDate not supplied

Complications with infection and foreign body reaction after silicon implant arthroplasty in the second metatarsophalangeal joint in an adolescent: a case report.

A 21-year-old otherwise healthy male was referred to our clinic due to severe pain, deformation, development of fistules, and swelling of the second metatarsophalangeal joint of the right foot. He presented a history of two previous operations. At the age of 13, a 2-cm. resection of the distal part of the proximal phalanx was performed due to severe hammertoe deformity. At the age of 19, a partial phalanx resection and implantation of a silicon elastomer ball-shaped joint spacer was performed due to second metatarsophalangeal joint instability. After this operation, the patient suffered from fistules that appeared in the second metatarsophalangeal region. Following referral to our clinic, the patient was operated on. The proximal phalanx was removed along with the prosthesis which had slipped from the metatarsophalangeal joint into the proximal phalanx with the ends of the prosthesis perforating the skin. Debridement of infected tissue and implantation of gentamicin containing beads were performed. Bacterial specimens revealed growth of coagulase-negative staphylococci. Microscopic examination of the debrided tissue showed signs of acute and chronic inflammation. Postoperatively, the patient was treated with antibiotics and healing was uneventful. This case advocates the need for proper selection criteria and strict indications in patients with joint disease needing an arthroplasty.

Adolescent↗
PubMed1994

Mechanoreceptor endings in human cervical facet joints.

Twenty-one cervical facet capsules, taken from three normal human subjects, were examined to determine the type, density, and distribution of mechanoreceptive nerve endings in these tissues. Clearly identifiable mechanoreceptors were found in 17 of 21 specimens and were classified according to the scheme for encapsulated nerve endings established by Freeman and Wyke. Eleven Type I, 20 Type II, and 5 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, lamellated capsule. Type III receptors were relatively large oblong structures with an amorphous capsule, within which a reticular meshwork of fine neurites was embedded. Free (nociceptive) nerve endings were found in subsynovial loose areolar and dense capsular tissues. The presence of mechanoreceptive and nociceptive nerve endings in cervical facet capsules proves that these tissues are monitored by the central nervous system and implies that neural input from the facets is important to proprioception and pain sensation in the cervical spine. Previous studies have suggested that protection muscular reflexes modulated by these types of mechanoreceptors are important in preventing joint instability and degeneration. It is suggested that the surgeon take steps to avoid inadvertently damaging these tissues when exposing the cervical spine.

Cervical Vertebrae↗
PubMed1983

Localization of bone-seeking agents in developing, experimentally induced osteoarthritis in the knee joint of the rabbit.

In order to elucidate the uptake and localization of bone-seeking agents in early and advanced osteoarthritis, bone scintigraphy and contact autoradiography were employed in experimental rabbit osteoarthritis, induced by joint instability of the knee. 42 adult rabbits were examined after administration of 99mTc-methylene diphosphonate given intravenously 1, 2, 4, 6, 12, 26 weeks and 1 1/2-2 years postoperatively, 6 animals at each interval. The scintimetric ratio between uptake in the unstable joint vs. control joint had P6creased as early as one week postoperatively and was highest within the first 3 months. The autoradiograms revealed two localizations of increased 99mTc-MDP uptake during different stages in osteoarthritic development: early uptake in growing osteophytes and late uptake in subchondral bone. The uptake in the osteophytes was localized to the provisional calcifications of enchondral ossification and could be observed as early as one week postoperatively, before there was any radiographic sign of osteophytes. The osteophytic uptake was responsible for the highest scintimetric ratios registered, but in the advanced state most osteophytes had lost their earlier increased uptake. The late subchondral uptake was seen mostly in the medial compartment of the joint under denuded or eburnated articular surfaces. The results provide a better understanding of the topography of bone scintigraphic uptake in osteoarthritis and indicate that early osteophytic growth is the cause of increased bone scintigraphic uptake in joints free from radiographic signs of osteoarthritis.

Animals↗
PubMed2005

Thermal capsulorrhaphy for isolated posterior instability of the glenohumeral joint without labral detachment.

BACKGROUND: Posterior instability of the glenohumeral joint is uncommon, and a minimally invasive, technically easy method of treatment with consistent results has not been reported. HYPOTHESIS: Thermal capsulorrhaphy for posterior instability with a period of postoperative immobilization will satisfactorily reestablish shoulder stability. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A total of 15 shoulders (13 patients) with isolated posterior instability without labral detachment were treated with thermal capsulorrhaphy. Eleven shoulders were immobilized for 6 weeks after surgery; 14 shoulders were clinically evaluated at a mean of 36 months (range, 26-53 months) after surgery. Of these patients, 2 (3 shoulders) had declined postoperative immobilization. RESULTS: Eleven shoulders were rated as excellent or good, and 3 experienced recurrent instability and were considered failures. The 3 failures occurred in 1 of 11 shoulders that were immobilized and 2 of 3 (in the same patient) that were not immobilized postoperatively. CONCLUSION: Thermal capsulorrhaphy for posterior instability of the glenohumeral joint, followed by 6 weeks of postoperative immobilization, restored glenohumeral stability in this group of patients.

Adolescent↗