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At least 109 records · Page 6Linked to original sources
PubMed1998

Capacity of the clinical picture to characterize low back pain relieved by facet joint anesthesia. Proposed criteria to identify patients with painful facet joints.

STUDY DESIGN: Prospective randomized study to compare the efficacy of facet joint injection with lidocaine and facet joint injection with saline in two groups of patients with low back pain, with and without clinical criteria that were determined in a previous study to implicate the facet joint as the primary source of the pain. OBJECTIVES: To assess the efficacy of single facet joint anesthesia versus placebo (saline injections) and to determine clinical criteria that are predictive of significant relief of LBP after injection. SUMMARY OF BACKGROUND DATA: There is no syndrome that discriminates between lower back pain caused by facet joint and that caused by other structures. Single or double facet joint anesthesia, and single photon emission computed tomography are expensive and time-consuming procedures for selecting patients in controlled clinical trials with large populations. METHODS: Results of a previous study showed that seven clinical characteristics were more frequent in patients who responded to facet joint anesthesia than in those who did not. In the current study, a group of 43 patients with lower back pain who met at least five criteria were compared with 37 patients who met fewer criteria. Patients randomly received injection of either lidocaine or saline into the lower facet joints. The result was considered positive if more than 75% pain relief was determined by visual analog scale. The patient, the radiologist, and the investigator were blinded. An analysis of variance was used to seek an interaction between clinical group effect and injection effect, and logistic regression analysis to select the best set of variables that would be predictive of minimum pain relief of 75% after the injection. RESULTS: There was a significant interaction between clinical group and injection effect (P = 0.003). In patients with back pain, lidocaine provided greater lower-back pain relief than saline (P = 0.01). Lidocaine also-provided greater pain relief in the back pain group than in the nonpain group (P = 0.02). The presence of five among seven variables (age greater than 65 years and pain that was not exacerbated by coughing, not worsened by hyperextension, not worsened by forward flexion, not worsened when rising from flexion, not worsened by extension-rotation, and well-relieved by recumbency), always including the last item, distinguished 92% of patients responding to lidocaine injection and 80% of those not responding in the lidocaine group. CONCLUSIONS: A set of five clinical characteristics can be used in randomized studies to select lower back pain that will be well relieved by facet joint anesthesia. These characteristics should not, however, be considered as definite diagnostic criteria of lower back pain originating from facet joints.

Adult↗
PubMed1981

[Studies on the cervical facet joints using arthrography of the cervical facet joint (author's transl)].

In order to elucidate the pathological changes of the cervical facet joint probably representing one of the causes of the neck and shoulder pain, the author developed the arthrography of the cervical facet joint and applied this method to 157 joints of 83 patients. Eight cadavers were also used to evaluate the method based on an anatomical basis. Cervical facet joints of patients with tenderness on the lateral side of the neck were studied. The technic used in this method using X-ray T.V. was described and the arthrograms obtained on the dissected specimens were compared with the anatomical findings. The arthrogram of the middle and lower cervical facet joint was classified into the type with regular joint margin, the type with slightly irregular one and the type with irregular one, or the type with sharp lateral margin and the type with unsharp one. In 80% of the 142 joints in total, a communicating pathway was found from the facet joint to the interlaminar portion, interspinous portion, contralateral facet joint, para-extradural space and cervical extradural space. These arthrograms were analyzed. The visualization of the atlanto-axial joint was also achieved. Even in normal subject, a communication to the contralateral side via the surface of the axial spine was demonstrated.

Adolescent↗
PubMed1997

Lumbar facet joint tropism does not accelerate degeneration of the facet joints.

PURPOSE: To study the relationship of lumbar facet joint tropism to degeneration of the cartilage and subcortical bone in the facet joints and the effect of tropism in intervertebral disk degeneration. METHODS: The orientation of 104 cadaveric lumbar facet joints with respect to sagittal plane was measured on CT scans, and the joints were classified as having no tropism, mild tropism, or severe tropism. On MR images, the severity of cartilage degeneration and bony sclerosis was measured. The correlation between tropism and degeneration was calculated, as was the relationship among age, spinal level, and degeneration. RESULTS: We identified four spinal levels with severe tropism, six with moderate tropism, and 94 without tropism. Cartilage degeneration was not significantly more severe in the joints with tropism than in the joints without. Sclerosis was slightly greater in the joints with tropism than in the joints without it. Sclerosis and cartilage degeneration were significantly related to age and spinal level. CONCLUSION: Age, spinal level, and overall facet joint angle are more important factors in facet joint degeneration than is tropism.

Adult↗
PubMed2000

Computer-based methods for measuring joint space and estimating erosion volume in the finger and wrist joints of patients with rheumatoid arthritis.

OBJECTIVE: This study was conducted 1) to determine the feasibility of using computer programs to measure radiographic joint space width and estimate erosion volume in the hands of patients with rheumatoid arthritis (RA), and 2) to compare the new computer-based methods with established scoring methods. METHODS: To measure the joint space width in the finger and wrist joints of RA patients, hand and wrist radiographic films were scanned using a tabletop scanner and analyzed with programs written using the "macro" capabilities of NIH Image software. Estimation of erosion volume was determined by utilizing gray-scale intensity to calibrate bone density units per mm3, which made possible comparisons between the erosions and noneroded, anatomically similar sites. RESULTS: In 3 sets of duplicate measurements of joint space width on 79, 48, and 48 finger and wrist joints, the mean absolute deviation from the mean of the 2 measurements was 0.036 mm (SD 0.034), 0.032 mm (SD 0.049), and 0.021 mm (SD 0.016), respectively. Joint space measurements and scoring of joint space narrowing both demonstrated a difference between active treatment and placebo in an old trial set on gold therapy (P = 0.03 and P = 0.01, respectively). Two repeated measurements of bone density units in the bones of 3 different hands differed from the mean of the measurement by 2.29-4.04%. In 2 experiments, estimates of erosion volume showed a greater difference between gold therapy and placebo than did erosion scores in the trial set (P = 0.049 and P = 0.016 versus P = 0.27). CONCLUSION: Computer-based methods for measuring finger and wrist joint spaces and estimating erosion volume in patients with RA agree with the results of radiographic scoring of erosions and joint space narrowing.

Arthritis, Rheumatoid↗
PubMed2006

Total joint arthroplasty in the treatment of advanced stages of thumb carpometacarpal joint osteoarthritis.

PURPOSE: Osteoarthritis of the thumb basal joint is a very common and disabling condition that frequently affects middle-aged women. Many different surgical techniques have been proposed for extensive degenerative arthritis of the first carpometacarpal (CMC) joint. Joint replacement has been an effective treatment of this condition. The purpose of this article is to present the outcome of a total cemented trapeziometacarpal implant in the treatment of more advanced stages of this disease. METHODS: Total joint arthroplasty of the trapeziometacarpal joint was performed on 26 thumbs in 25 patients to treat advanced osteoarthritis (Eaton and Littler stages III and IV) between 1998 and 2003. Indications for surgery after failure of conservative treatment were severe pain, loss of pinch strength, and diminished thumb motion that limited activities of daily living. A trapeziometacarpal joint prosthesis was the implant used in this series. The average follow-up time was 59 months. RESULTS: At the final follow-up evaluation, thumb abduction averaged 60 degrees and thumb opposition to the base of the small finger was present. The average pinch strength was 5.5 kg (85% of nonaffected side). One patient had posttraumatic loosening, which was revised with satisfactory results. Radiographic studies at the final follow-up evaluations did not show signs of atraumatic implant loosening. One patient complained of minimal pain, and the remaining 24 patients were pain free. CONCLUSIONS: In our series, total joint arthroplasty of the thumb CMC joint has proven to be efficacious with improved motion, strength, and pain relief. We currently recommend this technique for the treatment of stage III and early stage IV osteoarthritis of the CMC joint in older patients with low activity demands. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Aged↗
PubMed1997

Autologous fat transplantation around temporomandibular joint total joint prostheses: preliminary treatment outcomes.

PURPOSE: This study evaluated the efficacy of autologous fat grafting to the temporomandibular joint (TMJ) as an adjunct to prosthetic joint reconstruction in preventing fibrosis and heterotopic bone formation and determined its effects on postoperative joint mobility. PATIENTS AND METHODS: Fifteen patients (2 male, 13 female) underwent TMJ reconstruction with Techmedica (Techmedica, Inc, Camarillo, CA) custommade total joint prostheses. Seven patients had bilateral and eight had unilateral surgery, for a total of 22 joints. All patients had autologous fat from the abdomen grafted around the articulating portion of the joint prostheses after the fossa and mandibular components had been stabilized. Twenty patients (2 male, 18 female) without fat grafts served as controls. There were 17 bilateral and 3 unilateral cases, for a total of 37 joints. These were the last 20 patients with adequate data available for inclusion treated before patients receiving primary fat grafting as part of the joint reconstruction. RESULTS: In the control group, the average preoperative maximum interincisal opening (MIO) was 26.8 mm, and at long-term follow-up it was 33.1 mm. Contralateral excursive movements averaged 3.2 mm preoperatively and 1.7 mm at long-term follow-up. In the fat graft group, average preoperative MIO was 26.9 mm, and at long-term follow-up it was 38.7 mm. Contralateral excursive movements averaged 2.3 mm preoperatively and 2.2 mm at long-term follow-up. The differences in measured function between the two groups were found to be statistically significant (P < or = .01). Although both groups experienced a significant decrease in pain, there was no significant difference noted in the patients' perception of their level of pain at long-term follow-up as expressed on visual analog scale evaluations. There was no radiographic or clinical evidence of heterotopic calcifications or limitation of mobility secondary to fibrosis in any of the experimental groups, whereas seven control patients (35%) exhibited this phenomenon and required reoperation. CONCLUSIONS: Autologous fat transplantation appears to be a useful adjunct to prosthetic TMJ reconstruction. Its use appears to minimize the occurrence of excessive joint fibrosis and heterotopic calcification, consequently providing improved range of motion.

Adipose Tissue↗
PubMed2001

Knee joint mobilization reduces secondary mechanical hyperalgesia induced by capsaicin injection into the ankle joint.

Joint mobilization is a treatment approach commonly used by physical therapists for the management of a variety of painful conditions. However, the clinical effectiveness when compared to placebo and the neurophysiological mechanism of action are not known. The purpose of this study was to establish that application of a manual therapy technique will produce antihyperalgesia in an animal model of joint inflammation and that the antihyperalgesia produced by joint mobilization depends on the time of treatment application. Capsaicin (0.2%, 50 microl) was injected into the lateral aspect of the left ankle joint and mechanical withdrawal threshold assessed before and after capsaicin injection in Sprague-Dawley rats. Joint mobilization of the ipsilateral knee joint was performed 2 h after capsaicin injection for a total of 3 min, 9 min or 15 min under halothane anaesthesia. Control groups included animals that received halothane for the same time as the group that received joint mobilization and those whose limbs were held for the same duration as the mobilization (no halothane). Capsaicin resulted in a decreased mechanical withdrawal threshold by 2 h after injection that was maintained through 4 h. Both 9 and 15 min of mobilization, but not 3 min of mobilization, increased the withdrawal threshold to mechanical stimuli to baseline values when compared with control groups. The antihyperalgesic effect of joint mobilization lasted 30 min. Thus, joint mobilization (9 or 15 min duration) produces a significant reversal of secondary mechanical hyperalgesia induced by intra-articular injection of capsaicin.

Animals↗
PubMed2003

Long-term results of free vascularized second toe joint transfers to finger proximal interphalangeal joints.

PURPOSE: To review the long-term clinical results of free vascularized second toe joint transfers for severely damaged finger proximal interphalangeal (PIP) joints. METHODS: Eleven joints in ten patients (1 woman, 9 men) were reviewed between 10 and 22 years after surgery. The average patient age at the time of the surgery was 32 years. Patients were evaluated at a mean follow-up time of 15 years; evaluation included range of motion of the transferred PIP joints and the remaining healthy second toe PIP joints, grip strength, finger and toe pain, finger function, gait disturbance, patient satisfaction, and x-ray changes. RESULTS: The mean active range of motion was 47 degrees that lacks 41 degrees extension and flexes to 88 degrees. The mean grip strength was more than 80% that of the nonaffected hand, and no finger pain or gait disturbances were reported. All patients had some extension lag and flexion contractures but most were satisfied with the clinical and functional results of surgery. In all joints, the joint spaces were preserved, although 1 patient had arthritis and 3 had osteophytes. CONCLUSIONS: It is important to prevent extension lag and flexion contracture to get better results from free vascularized second toe joint transfers. The transferred toe PIP joint is durable.

Adult↗
PubMed1993

Joint hyperlaxity and its long-term effects on joints.

The range of movement at a joint varies between individuals. Reasons for this include inherited collagen structure in the joint capsule and ligaments, inherited shape of the bony articulating surfaces and neuromuscular tone which may be acquired and is modified by training. Methods for quantifying the range of movement at joints are described and compared, including the hyperextensometer and the Carter and Wilkinson score. Clinical patterns of joint hyperlaxity and their correlation with aetiology are discussed. Joint hyperlaxity may be advantageous in certain sports. Coaches need to be aware of optimum methods for improving it as well as for guarding against injury. Conversely, physiotherapists may learn from sports physiologists in the management of symptoms arising from patients who have hyperlax joints. Joint stability reduces the risk of injury. Joint hyperlaxity may also be associated with premature osteoarthritis but this is not always so. Joint instability may be the most potent cause though a radiological survey of retired teachers of physical education conducted by our Unit failed to show a higher incidence of osteoarthritis after a life spent in sport than in sedentary controls. However, certain factors that place some individuals at particular risk were identified.

Humans↗
PubMed1991

Frequency of bilateral temporomandibular joint disc displacement in patients with unilateral symptoms: a 5-year follow-up of the asymptomatic joint. A clinical and arthrotomographic study.

Bilateral arthrotomography was performed in 50 consecutive patients with unilateral symptoms of disc displacement to evaluate the frequency of temporomandibular joint disc displacement in asymptomatic joints. Using well-defined clinical criteria, there were no false-positive findings of either reducing or non-reducing discs. On the other hand, a risk of false-negative diagnosis of non-reducing disc was apparent. Sixty per cent of the patients had a non-reducing displaced disc in the asymptomatic joint. Most of these patients could recall a previous spell of discomfort from this joint. Severe or moderate deformation had taken place in non-reducing discs, while reducing discs were normal in shape or had, at most, a thickening of the posterior band. The duration of symptoms was significantly correlated with the degree of deformation in the symptomatic joints (P less than 0.01). Perforation was statistically, significantly correlated with disc deformation and, in symptomatic joints, hard tissue changes. Fifty-seven per cent of the asymptomatic joints with displaced discs developed pain following the onset of symptoms from the contralateral side, most within 2 years. Less than half of them were free of pain at the end of the 5 year follow-up period. In view of this tendency for an asymptomatic joint with a displaced disc to subsequently develop pain refractory to treatment, such a joint must be considered a weakened link in the craniomandibular system, vulnerable to changes in mandibular function such as, for instance, displacement of the disc on the contralateral side.

Adolescent↗
PubMed2002

Morphometrical study of the joint surface and capsule of the lumbar zygapophysial joint with special reference to their laterality.

Using 26 osteoligamentous lumbar vertebral columns (260 facets), we morphometrically investigated the cartilagenous joint surface, inner capsular surface and capsular thickness. We also examined whether the subcapsular pocket was present and, if present, how far it extended along the joint margin. The proportion of the inner capsular area in the total joint surface area in a facet (the capsular-joint surface ratio) was hypothesized to correspond to the potential looseness (or tightness) of the facet. The absolute data themselves seemed to be useful for better understanding of the joint morphology. However, further evaluations of the differences between segments, left/right differences, individual segmental fluctuation patterns and correlations between parameters provided a novel classification of specimens according to the hypothetical progress of joint degeneration. Criteria for the classification existed in 1) the laterality in parameters defined as more than 100% larger or smaller than the contralateral facet and 2) the drastic segmental difference in parameters over 50% larger or smaller than the adjacent segment. Consequently, three types were identified: 1) outside of the criteria in both area and thickness (-/- type, 9 of 26); 2) the criteria did not fit the area parameters but did fit the thickness parameters (-/+ type, 8); the criteria were filled in both categories of parameters (+/+ type, 9). Notably, in the +/+ types, the capsular thickness and capsular-joint surface ratio correlated significantly (p < 0.01), i.e., the hypothetical loose joint had a thick capsule. We speculated that early joint degeneration starts from the -/- type and advances via the -/+ type to the +/+ type. Considerating these results, we recommended using MR imaging for detailed identification of laterality in the capsular thickness for low-back pain patients to discriminate candidates for future severe degenerative changes of the articular cartilage in the lumbar spine.

Aged↗
PubMed2002

Limited joint mobility in selected hand and foot joints in patients with type 1 diabetes mellitus: a methodology comparison.

OBJECTIVES: First to determine the range of motion (ROM) of selected foot and hand joints with a goniometer, 2.) to determine joint limitation by prayer sign and 3.) to compare both methods used. METHODS: Maximal active ROM was measured by goniometry (Method 1) in 50 patients with Type 1 diabetes and in 44 healthy controls, respectively. The lower limits for normal ranges were defined as mean minus 2 SD. To elicit the prayer sign (Method 2) subjects were asked to put their hands together in a praying position with the fingers fanned. The number of missing joint contacts between the fingers was counted and correlated to ROM. RESULTS: The ROM of all joints measured, except that of the thumb, was significantly smaller in diabetic patients than in control subjects. The degree of the prayer sign was well correlated to the ROM of most hand joints, but was solely correlated in feet to ankle ROM. In diabetic patients the prevalence of limited joint mobility (LJM) measured by goniometry ranged from 2 to 20% in hand joints and from 10 to 14% in foot joints. By the prayer sign 33% of the diabetic patients had LJM. CONCLUSION: With both methods, diabetic patients had more limitations in joint motion than control subjects, as was their prevalence of LJM higher. Since the prayer sign was correlated to exactly measured ROMs, we would suggest using the prayer sign as a simple clinical indicator for LJM in diabetic subjects.

Adult↗
PubMed2002

The incidence of reoperation after temporomandibular joint arthroscopic surgery: a retrospective study of 450 consecutive joints.

PURPOSE: The purpose of this study was to investigate the incidence of reoperation after temporomandibular joint arthroscopic surgery in 315 consecutive patients (488 joints). STUDY DESIGN: The clinical data and operative reports of all patients who underwent arthroscopic procedures from 1995 to 2000 were reviewed retrospectively. Patients had a preoperative clinical and panoramic radiographic evaluation. Most of the patients had disk displacement without reduction. In the remaining patients, the intra-articular pathologic conditions ranged from disk displacement with reduction to degenerative joint disease. The outcome assessment was based on reduction in pain, improvement in vertical dimension of mouth opening, and mandibular excursions. The same surgical team performed all arthroscopic procedures. Before surgery, all patients received at least 3 to 6 months of nonsurgical therapy consisting of anti-inflammatory medications, muscle relaxants, splint therapy, physiotherapy, exercise, moist heat, cold laser, ultrasound, and soft diet or a combination thereof. Patients were monitored postoperatively for as long as 5 years. RESULTS: Results showed that approximately 20% of those patients who had temporomandibular joint arthroscopic surgery underwent further temporomandibular joint procedures ranging from repeat arthroscopic surgery to open-joint arthrotomy. CONCLUSION: Temporomandibular joint surgical arthroscopy is an appropriate therapeutic modality for patients with temporomandibular joint internal derangements, with reoperation required for only 20% of patients.

Adolescent↗
PubMed2003

Does joint effusion on T2 magnetic resonance images reflect synovitis? Part 3. Comparison of histologic findings of arthroscopically obtained synovium in internal derangements of the temporomandibular joint.

OBJECTIVES: To evaluate the relationship between the volume of joint effusion (JE), determined by T2-weighted magnetic resonance imaging (MRI), and microscopic findings of synovial inflammation in internal derangement of the temporomandibular joint (TMJ). STUDY DESIGN: Magnetic resonance images of 53 symptomatic TMJs (53 patients) associated with painful hypomobility were taken to evaluate the degree of JE on a scale of 0 to 3. Within 2 months after MRI, biopsy specimens obtained by arthroscopy were quantitatively assessed, on the basis of Gynther's grading system, for severity of hyperplasia of synovial lining cell layers, vascularity, and the presence of inflammatory cells. Each synovitis score was compared among the 4 JE grades, as well as between 2 groups-effusion present (grades 2 and 3) and effusion absent (grades 0 and 1)-by using the Spearman correlation coefficiency and the Mann-Whitney U test. RESULTS: The distribution of JE was as follows: 14 joints had grade 0, 9 joints had grade 1, 19 joints had grade 2, and 11 joints had grade 3. Significant relationships were found between the grades of JE and scores of synovial lining cell layers (P =.0012) as well as between the grades of JE and scores of presence of inflammatory cells (P =.0064). The joints with effusion had significantly higher scores for synovial lining cell layers (2.0 +/- 0.2) than the joints without effusion (1.3 +/- 0.2) (P =.029). There was no statistically significant correlation between the scores of vascularity and JE (P =.394). CONCLUSIONS: The evidence of JE on MRI might correlate with synovial inflammatory activity. It confirms the common consensus that JE probably reflects synovitis, especially when synovial hyperplasia has a key role in the pathogenesis of JE.

Adolescent↗
PubMedDate not supplied

Magnetic resonance evidence of joint fluid with temporomandibular joint disorders.

OBJECTIVES: The relationship between temporomandibular joint (TMJ) effusion and TMJ disorders is controversial. The frequency of TMJ effusion has varied as shown in previous studies. Furthermore, though some authors have suggested a correlation between TMJ effusion and pain, others question the relationship. In order to clarify the relationship, it is necessary to quantify the degree of effusion and thoroughly investigate its relationship to other factors. The purpose of this study was to analyze the amount of TMJ fluid present in joints with TMJ disorders and to see how TMJ effusion is related to TMJ status and pain. METHODS: We studied 577 joints in 293 patients referred to us for magnetic resonance imaging. The joints were divided into painful and nonpainful categories and also classified according to Westesson's criteria for the status of the TMJ. The grading system of Larheim et al was used for categorizing the amount of fluid. Statistical methods were used for analyzing the relationship between TMJ fluid and TMJ status and pain. RESULTS: TMJs with disk displacement without reduction showed the largest amount of fluid while TMJs with normal superior disk position showed the least fluid (Kruskal-Wallis test, P<0.001; Scheffe test, P<0.001). There was a significant difference in the amount of the fluid between painful and nonpainful joints in the group of disk displacement without reduction (Wilcoxon rank sum test, P<0.001). No significant differences were found between other groups. CONCLUSIONS: Joint effusion is likely to appear in painful TMJs with disk displacement without reduction. Joint effusion may be an abnormal entity just suited to joints with disk displacement without reduction.

Adult↗
PubMed1995

Collagen gene expression during development of avian synovial joints: transient expression of types II and XI collagen genes in the joint capsule.

The developmental sequence of the embryonic joint has been well studied morphologically. There are, however, no definitive studies of cell function during joint development. In order to begin to understand the differentiation events that contribute to joint formation, we examined the expression of collagen mRNAs encoding types I, IIA, IIB, and XI. In situ hybridization was performed on chicken embryo hind limb buds and digits from day 7 to day 18 (Hamburger and Hamilton stages 31-44). In the day 7 (stage 31) limb bud, there was a condensation of mesenchyme forming the primitive tarsal and metatarsal bones that showed abundant expression of type IIA procollagen message, but no type IIB or type alpha 1(XI) message. By day 8 (stage 33), co-expression of types IIA, and type XI procollagen mRNAs was observed in the condensations, with expression of IIB restricted to early chondrocytes with metachromatically staining matrix. At this stage, DNA fragmentation characteristic of apoptosis was observed in cells near the midline of the interzone region between the developing anlagen, and in areas between and around the individual digits of the paddle. The presumptive apoptotic cells were more numerous at day 9 (stage 35), and were not found in the developing joint at subsequent time points, including the initiation of spatial cavitation of the joint. From days 11-18, type IIA procollagen mRNA was expressed in flattened cells at the surface of the anlagen, and in the perichondrium and in the developing joint capsule; type IIB mRNA message was found only in chondrocytes. Type XI mRNA was expressed by all type II-expressing cells. Alpha 1(I) mRNA was expressed early by cells of the interzone and capsule, but as cavitation progressed, the type I expressing cells of the interzone merged with the superficial layer of the articular surface. Thus, at the time of joint cavitation, there was a distinct pattern of expression of procollagen messages at the articular surface, with type I being outermost, followed by morphologically similar cells expressing type IIA, then chondrocytes expressing type IIB. The progenitor cells expressing type IIA message define a new population of cells. These cell populations contribute to the molecular heterogeneity of the articular cartilage, and these same populations likely exist in the developing joints of other species. The transient transcription of type II and type XI collagen genes, characteristic of chondrocytes, by cells in the joint capsule demonstrates that these cells may have chondrogenic potential.

Animals↗
PubMed1995

Morphomechanics of the humero-ulnar joint: I. Joint space width and contact areas as a function of load and flexion angle.

BACKGROUND: Previous studies have shown that the trochlear notch is deeper than necessary for an exact fit with the humerus. However, humero-ulnar joint space width and contact areas have so far not been quantified for variations in the load and angle of flexion. METHODS: Six fresh cadaveric specimens were investigated at 30 degrees, 60 degrees, 90 degrees, and 120 degrees of flexion and at loads of 25 and 500 N, simulating resisted elbow extension. The joint space width and contact were determined, using polyether casting material. RESULTS: At 25 N all joints made contact in the ventral and dorsal aspects of the articular surfaces, whereas in the depth of the trochlear notch the joint space was on average between 0.3 and 2.8 mm wide, with some variation between individuals. At 500 N the joint space width was considerably reduced and the contract areas expanded towards the depth of the notch. The size of the dorsal contact areas was significantly smaller at 30 degrees and that of the ventral ones at 120 degrees, their ventro-dorsal ratio decreasing considerably from 30 degrees to 120 degrees (p < 0.01). CONCLUSION: These results indicate that the size of the contact areas depends to a slight extent on the joint position, but that at all loads and flexion angles a bicentric contact and an important central joint space width emerge because of the concave incongruity of the joint. These data may be used for numerical calculations, analysing the effects of incongruity on the joint stress and on the functional adaptation of the subarticular tissues.

Adult↗
PubMed2003

Stability of inter-joint coordination during circle drawing: effects of shoulder-joint articular properties.

The present study addressed the effect of articular conformity of the shoulder joint on the stability of inter-joint coordination during circular drawing movements. Twelve right-handed participants performed clockwise and counter-clockwise circular drawing movements at nine locations in the mid-sagittal plane. The task was paced acoustically at 1.0, 1.5 and 2.0 Hz and performed without visual control. Displacements of seven infrared light emitting diodes that were fixated at relevant joints were sampled at 100 Hz by means of a 3D-motion tracking system (Optotrak 3020). From these data, shoulder, elbow and wrist angular excursions were derived as well as the continuous relative phase of the proximal and distal joint pairs of the arm. The results confirmed earlier observations that the shoulder and elbow are more strongly coupled than the elbow and wrist in sagittal-plane movements. However, a typical characteristic of the architecture of the shoulder joint, that is, its built-in mechanical "joint play", was shown to induce a position-dependent variation in inter-joint coordination stability. We conclude that besides polyarticular-muscle induced synergies and inertial coupling, articular conformity of the shoulder joint constitutes an additional determinant of inter-joint coordination stability that, to date, has been neglected.

Adolescent↗