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At least 505 records · Page 28Linked to original sources
PubMed1989

Two-and three-dimensional imaging of the painful shoulder.

Fifty-six patients with musculoskeletal disorders involving the shoulder were examined using two-dimensional computed tomography multiplanar reconstruction and volumetric three-dimensional (3D) image processing. Two- and three-dimensional imaging of the shoulder demonstrated advantages over conventional radiography in clarifying areas of complex anatomy. The techniques were found most beneficial for (1) delineating complex fractures; (2) evaluating joint instability; (3) localizing foreign bodies; (4) detecting lytic lesions; (5) assessing soft tissue pathology; and (6) identifying causes for decreased range of motion. Two-dimensional multiplanar reconstruction provided superior views of the scapula and permitted a better understanding of the orientation of the glenoid. Multiplanar reconstruction displayed deep soft tissue anatomy more clearly, including the course of important neurovascular structures. Volumetric 3D imaging added several unique perspectives, providing a more comprehensive representation of the shoulder and its articulating surfaces. The ability to rotate the shoulder about he vertical and horizontal axes in an animated video loop and to edit away confusing, overlying structures provided a "real-time" 3D model of the shoulder for planning treatment.

Humans↗
PubMed1991

[Errors in reconstructive-rehabilitative operations on the hip joint].

Based upon the analysis of 1015 case records of patients, aged 16-70, with different hip joint pathology types, carried out during 1985-1990, there were revealed mistakes and complications after reconstructive-restorative operations. In the group of patients with dysplastic coxarthrosis they noted rather frequent (12% of cases) formation of "tectum" in supratrochanteric region that served as the cause of joint instability and development of arthrosis in future. Cartilaginous limbus, not removed at grave forms of dysplastic coxarthrosis, served as the cause of the pain syndrome in 63% of cases. Carrying out of "osteotomy-medicate" only in patients with aseptic necrosis of femoral head was ineffective in 38% of cases. Total removal of necrotization foci in thigh head with subsequent osseous plasty is necessary. In the process of mobilization operation in case of hyperplastic, coxarthrosis, removal of the lower edge of cotyloid cavity is the obligatory step. Thus, the important condition of favourable terminations of reconstructive-restorative operations is the correct selection of indications, carrying out of complete surgical intervention, rigorous observation of the patient control rules in near and distant postoperative period.

Adolescent↗
PubMed2006

Altered neuromuscular control and ankle joint kinematics during walking in subjects with functional instability of the ankle joint.

BACKGROUND: The ankle joint requires very precise neuromuscular control during the transition from terminal swing to the early stance phase of the gait cycle. Altered ankle joint arthrokinematics and muscular activity have been cited as potential factors that may lead to an inversion sprain during the aforementioned time periods. However, to date, no study has investigated patterns of muscle activity and 3D joint kinematics simultaneously in a group of subjects with functional instability compared with a noninjured control group during these phases of the gait cycle. PURPOSE: To compare the patterns of lower limb 3D joint kinematics and electromyographic activity during treadmill walking in a group of subjects with functional instability with those observed in a control group. STUDY DESIGN: Controlled laboratory study. METHODS: Three-dimensional angular velocities and displacements of the hip, knee, and ankle joints, as well as surface electromyography of the rectus femoris, peroneus longus, tibialis anterior, and soleus muscles, were recorded simultaneously while subjects walked on a treadmill at a velocity of 4 km/h. RESULTS: Before heel strike, subjects with functional instability exhibited a decrease in vertical foot-floor clearance (12.62 vs 22.84 mm; P < .05), as well as exhibiting a more inverted position of the ankle joint before, at, and immediately after heel strike (1.69 degrees , 2.10 degrees , and -0.09 degrees vs -1.43 degrees , -1.43 degrees , and -2.78 degrees , respectively [minus value = eversion]; P < .05) compared with controls. Subjects with functional instability were also observed to have an increase in peroneus longus integral electromyography during the post-heel strike time period (107.91%.millisecond vs 64.53%.millisecond; P < .01). CONCLUSION: The altered kinematics observed in this study could explain the reason subjects with functional instability experience repeated episodes of ankle inversion injury in situations with only slight or no external provocation. It is hypothesized that the observed increase in peroneus longus activity may be the result of a change in preprogrammed feed-forward motor control.

Ankle Joint↗
PubMed1995

Treatment of dogs with wounds of the limbs caused by shearing forces: 98 cases (1975-1993).

Medical records of 98 dogs with wounds of the limbs caused by shearing forces (shearing wounds) were reviewed. Shearing wounds were reported most often in young dogs of many breeds, and most often resulted from trauma received during an encounter with an automobile. Wounds were located mainly on the distal portion of the limbs, with the most common site being the medial aspect of the tarsus and metatarsus. All injuries resulted in exposure of subcutaneous soft tissues, about three fourths of all injuries resulted in bone or joint exposure, and slightly more than half of the dogs had joint instability. All wounds were lavaged and debrided. Wounds were sutured, using primary closure techniques or methods that allowed the wound to remain partially or totally open to heal by second intention. Bandages were applied in all dogs. Most bandages were reinforced with a splint device. Grafting procedures or internal fixation devices were not used in initial treatment of the injuries. In the study reported here, healing time ranged from 2.0 to 8.7 weeks, depending on the size and depth of the wound and type of closure used. Mean number of anesthetic and surgical procedures was 1.7 per dog, and the mean number of rechecks after discharge from the hospital was 5.5 per dog. Outcome was considered excellent or good in 89 of 98 (91%) dogs; these dogs were clinically normal or had only minor functional abnormalities after their injuries healed. Outcome was poor in 9 of 60 (15%) dogs.

Accidents, Traffic↗
PubMed2005

Stability of implant-abutment interface with a hexagon-mediated butt joint: failure mode and bending resistance.

BACKGROUND: Clinical data showed that the external hexagon implant system with a gold abutment screw has reduced the problem of screw loosening or fracture. However, the behavior of the implant-abutment joint components with respect to unfavorable bending force is still unclear. PURPOSE: This study investigated the joint instability and bending resistance of a single-tooth external hexagon implant system after lateral cyclic loading. MATERIALS AND METHODS: Fifteen implant assemblies (Nobel Biocare, Göteborg, Sweden) were divided equally into three groups: A, B, and C. Each assembly consisted of a Brånemark System Mk IV implant (4 x 10 mm) mounted in a brass block, a CeraOne abutment (3 mm), and an experimental cement-retained superstructure. For group A, a centric lateral cyclic load of 50 N was applied for 1.0 x 10(6), whereas for group B, the same load was eccentrically applied for 1.0 x 10(6) cycles. Group C, the control, was not loaded. After cyclic loading, specimens were mounted in a universal testing machine, and the yield and bending strengths were measured (kg). The external hexagon surface texture was examined using a secondary electron microscope. The data were analyzed with one-way analysis of variance and compared by the Tukey test (alpha = .05). RESULTS: For all test specimens, the abutment screw was plastically bent in the unthreaded portion. Group B had a significantly lower mean yield and bending strengths than group C (p = .005 and .010, respectively). Post-cyclic loading photographs showed that group B implants had marked burnishing around the hexagon corners. The bending force abraded both corner areas of the hexagon surface but left the middle area nearly intact for all tested groups. However, group B had the significantly lowest mean abraded area. CONCLUSION: Within the limits of this study, eccentric rather than centric lateral cyclic loading negatively affected the resistance of the implant-abutment joint to static bending.

Dental Abutments↗
PubMed2005

Thermal damage prediction for collagenous tissues part I: a clinically relevant numerical simulation incorporating heating rate dependent denaturation.

Subablative thermotherapy is frequently used for the treatment of joint instability related diseases. In this therapy, mechanically deformed collagenous tissues are thermally shrunk and the stability of the tissue is re-established. In this research, the thermal damage fields generated by three different clinical heating modalities (monopolar and bipolar radio frequency and Ho:YAG laser) are compared numerically using finite element analysis. The heating rate dependent denaturation characteristics of collagenous tissues are incorporated into the model using experimental data from in vitro experimentation with rabbit patellar tendons. It is shown that there are significant differences among the thermal damage profiles created by these modalities, explaining the main reason for the discrepancies reported in the literature in terms of the efficacy and safety of each modality. In the complementary paper, the accuracy of the model presented here is verified by in vitro experimentation with a model collagenous tissue and by quantifying the denaturation-induced birefringence change using Optical Coherence Tomography and Magnetic Resonance Imaging.

Animals↗
PubMed2006

Fungal osteoarticular infections in patients treated at a comprehensive cancer centre: a 10-year retrospective review.

This study reviewed retrospectively the clinical characteristics of 28 cancer patients with fungal osteoarticular infections (FOAIs) between 1995 and 2005. Most patients (26; 93%) had haematological malignancies (19 had leukaemia); half (14) were allogeneic stem-cell transplant recipients. Twelve patients (43%) had severe neutropenia (< or = 100/mm3) with a mean duration of 65 days (range 10-500 days), and ten (36%) patients had received a significant dose of corticosteroids. Most (19; 68%) FOAIs were caused by contiguous extension, while nine (32%) were associated with haematogenous spread. Pain, joint instability and local drainage were seen in 28 (100%), six (21%), and seven (25%) patients, respectively. Sixteen (57%) patients had symptoms for < 1 month. The sinuses (ten; 36%) and the vertebral spine (six; 21%) were the most common sites involved. Moulds were the predominant pathogens: Aspergillus fumigatus (two); non-fumigatus Aspergillus spp. (eight); non-specified Aspergillus spp. (three); Fusarium spp. (six); Zygomycetes (five); Scedosporium apiospermum (two); and Exserohilum sp. (one). Candida was the causative pathogen in four cases (including two cases of mixed FOAIs). Arthritis and post-operative FOAIs were both uncommon manifestations, occurring in two patients each. All patients received systemic antifungal therapy (combinations in 20 cases), and 19 cases underwent adjunctive surgery. The crude mortality rates (at 12 weeks) were 44% (9/20) in the patients who underwent surgery and antifungal therapy vs. 33% (2/6) in patients who received antifungal therapy alone (p not significant). FOAI is a rare, yet severe, manifestation of localised or systemic mycoses, caused predominantly by moulds, and is seen typically in patients with haematological malignancies.

Adult↗
PubMed2000

Matrix metalloproteinase-13 expression in rabbit knee joint connective tissues: influence of maturation and response to injury.

The hypothesis of the present work was that expression of matrix metalloproteinase-13 (MMP-13, collagenase-3) would be induced during conditions involving important matrix remodeling such as ligament maturation, scar healing and joint instability. Therefore, MMP-13 expression in the medial collateral ligament (MCL) during the variable situations of tissue maturation and healing was assessed. MMP-13 expression in three intra-articular connective tissues of the knee (i.e. articular cartilage, menisci and synovium) following the transection of the anterior cruciate ligament of the knee was evaluated at 3 and 8 weeks post-injury. MMP-13 mRNA (semi-quantitative RT-PCR) and protein (immunohistochemistry and Western blotting) were detected in all of the tissues studied. Significantly higher MCL mRNA levels for MMP-13 were detected during the early phases of tissue maturation (i.e. 29 days in utero and 2-month-old rabbits) compared to later phases (5- and 12-month-old rabbits). This pattern of expression was recapitulated following MCL injury, with very high levels of expression in scar tissue at 3 weeks post-injury and then a decline to levels not significantly different from control values by 14 weeks. Elevated mRNA levels correlated with increased protein levels for MMP-13 in both menisci and synovium following the transection of the anterior cruciate ligament and during medial collateral ligament healing. These results indicate that MMP-13 expression is regulated by a number of variables and that high levels of expression occur in situations when connective tissue remodeling is very active.

Animals↗
PubMed2002

Factors Contributing to Chronic Ankle Instability: Kinesthesia and Joint Position Sense.

OBJECTIVE: To present a comprehensive review of the influence of altered kinesthesia and joint position sense on chronic ankle instability and to present a model connecting deficits in ankle position sense with the increased risk of sustaining lateral ankle sprains. DATA SOURCES: I searched MEDLINE for the years 1966-2001 using the key words ankle and kinesthesia or position sense and books on proprioception. DATA SYNTHESIS: Study findings suggest a risk for unprovoked lateral ankle sprains when the lateral border of the foot accidentally catches the ground surface during the late swing phase of normal locomotion. In normal situations, the lateral border of the foot clears the ground by only 5 mm, and a small increase in ankle-position error may substantially increase the risk of a collision. Findings of affected kinesthesia and joint position sense in subjects with chronically unstable ankles dominate over studies showing nonsignificant results, but the answer is far from clear. CONCLUSIONS/RECOMMENDATIONS: Changes in joint position sense and kinesthesia of a magnitude found in subjects with chronically unstable ankles can lead to an increased risk of sustaining lateral ankle sprains. Results from a small number of studies suggest that balance and coordination training can restore the increased uncertainty of joint positioning to normal levels.

Journal Article↗
PubMed2005

Graft reconstruction of the interosseous membrane in conjunction with metallic radial head replacement: a cadaveric study.

PURPOSE: Longitudinal radioulnar dissociation (Essex-Lopresti injury) occurs when traumatic axial loading through the wrist disrupts the interosseous membrane (IOM) of the forearm and fractures the radial head. Proximal migration of the radius results in an ulnar-positive wrist, which can lead to painful ulnar-sided wrist degeneration and distal radioulnar joint instability. The purpose of this study was to measure the ability of an IOM reconstruction used in combination with a metal prosthetic radial head implant to reduce distal ulnar forces in a cadaveric model. The effects of varying the initial graft pretension on distal ulnar force were also studied. METHODS: Twelve fresh frozen and thawed cadaveric forearms had a miniature load cell installed to record force in the distal ulna as the wrist was loaded axially to 134 N of compression force in neutral rotation. Intact forearms were tested first with the elbow in valgus and varus alignments. Loading tests were repeated after (1) insertion of a metal radial head implant that restored radius anatomic length, (2) excision of the IOM (with a radial head implant), and (3) reconstruction of the IOM using a palmaris longus tendon autograft (with a radial head implant). The implant then was removed and loading tests were repeated using 3 levels of initial graft pretension. RESULTS: Mean distal ulnar forces with an intact forearm were 23% of applied wrist force in the varus alignment and 12% in the valgus alignment. Mean force levels after insertion of the implant were 18% (varus) and 13% (valgus); these were not significantly different from corresponding values for the intact forearm. Mean force levels after section of the IOM were 30% (varus) and 14% (valgus); these were not significantly different from corresponding values for the intact forearm (varus and valgus) but the mean for varus was significantly greater than the corresponding value with an implant. After IOM reconstruction with a palmaris longus tendon tensioned to 22 N mean distal ulnar forces were 8% (varus) and 7% (valgus); these means were significantly less than the corresponding values for all prior test conditions. With the radial head removed increasing the level of graft pretension reduced significantly mean distal ulnar force. CONCLUSIONS: With the IOM resected insertion of a metal radial head implant alone did not reduce distal ulnar forces to intact forearm levels. When an IOM reconstruction was performed in combination with the implant mean distal ulnar force was reduced significantly to a level below that for the intact forearm. Applying pretension to the graft displaced the radius distally thereby making the wrist more ulnar negative and reducing distal ulnar force. Our results suggest that an IOM reconstruction used in combination with a metal radial head implant theoretically could help reduce distal ulnar impaction in an Essex-Lopresti injury.

Aged↗
PubMed1991

Surgical treatment of internal derangements of the temporomandibular joint. A long-term study.

A long-term surgical follow-up study of 176 patients (211 joints) with documented internal derangements of the temporomandibular joint was carried out. Arthrograms and tomograms were used in all cases. Forty of the patients (49 joints) were nonsurgical control patients. Diagnostic staging of the cases was accomplished as previously published. A clinical/radiologic assessment index was derived, which included seven measured parameters. Surgical patients, grouped by diagnostic stages and selected operations, were compared with each other and with control patients over the follow-up period (average, 8.1 years; range, 5 to 14 years). The surgical procedures included meniscectomy, reconstructive arthroplasty, and arthroplasty with temporary Silastic (Dow Corning Wright, Arlington, Tenn) implant. The overall success rate for surgical cases with all stages and procedures was 93.8%. In contrast, the control group demonstrated significant clinical and radiographic progression. The surgical results were stage dependent for the same operative procedure. Significantly better success rates were obtained in early-stage cases (96.9%) than in late-stage cases (89.4%). With respect to comparison of operative procedures, it was found that reconstructive arthroplasty provided results superior to those of meniscectomy. There was no significant difference between results obtained by meniscectomy and those by arthroplasty with a temporary Silastic implant. Long-term stability was excellent in most cases. Follow-up radiographic changes for the surgical group were less than expected. On the other hand, radiographic analysis of the control group demonstrated progressive degenerative changes in 73.5% of cases. Complications over the entire study were rare. It was concluded that surgery can provide successful long-term results in the treatment of internal derangements.

Adolescent↗
PubMed1997

Ehlers-Danlos syndrome type VIIA and VIIB result from splice-junction mutations or genomic deletions that involve exon 6 in the COL1A1 and COL1A2 genes of type I collagen.

Ehlers-Danlos syndrome (EDS) type VII results from defects in the conversion of type I procollagen to collagen as a consequence of mutations in the substrate that alter the protease cleavage site (EDS type VIIA and VIIB) or in the protease itself (EDS type VIIC). We identified seven additional families in which EDS type VII is either dominantly inherited (one family with EDS type VIIB) or due to new dominant mutations (one family with EDS type VIIA and five families with EDS type VIIB). In six families, the mutations alter the consensus splice junctions, and, in the seventh family, the exon is deleted entirely. The COL1A1 mutation produced the most severe phenotypic effects, whereas those in the COL1A2 gene, regardless of the location or effect, produced congenital hip dislocation and other joint instability that was sometimes very marked. Fractures are seen in some people with EDS type VII, consistent with alterations in mineral deposition on collagen fibrils in bony tissues. These new findings expand the array of mutations known to cause EDS type VII and provide insight into genotype/phenotype relationships in these genes.

Adult↗
PubMed2005

Cruciate ligament laxity and femoral intercondylar notch narrowing in early-stage knee osteoarthritis.

OBJECTIVE: The influence of the cruciate ligaments in spontaneous osteoarthritis (OA) is not understood, although ligament rupture is known to cause secondary OA. Additionally, femoral notch narrowing at the anterior cruciate ligament (ACL) insertion site is associated with disease severity, but it is unknown whether ligament deterioration precedes or follows osteophyte formation. We examined cruciate ligament mechanics and metabolism and the intercondylar notch width in OA-prone Dunkin-Hartley (DH) guinea pigs at ages up to and including the age at OA onset (24 weeks), and compared the data with those in age-matched controls (Bristol strain 2 [BS2] guinea pigs). METHODS: Guinea pigs were assessed at 3, 6, 9, 12, 16, 20, 24, and 36 weeks of age. ACLs were mechanically tested, and the intercondylar notch width index (NWI) was determined. Cruciate ligament metabolism was determined by measuring the following markers of collagen turnover: matrix metalloproteinase 2 (MMP-2), tissue inhibitor of metalloproteinases 2, C-terminal type I procollagen propeptide (PICP), and the immature collagen-derived crosslink dihydroxylysinonorleucine (DHLNL). RESULTS: DH guinea pigs had significantly laxer ACLs than did BS2 guinea pigs, at 12, 16, and 24 weeks. We observed elevated levels of pro and active MMP-2, PICP, and DHLNL in the cruciate ligaments of DH animals at most ages, compared with BS2 guinea pigs. The NWI in DH animals was significantly lower than that in BS2 guinea pigs at 24 and 36 weeks. CONCLUSION: In DH guinea pigs, laxer ACLs, which are associated with increased collagen turnover, may cause joint instability and predispose these animals to the early onset of OA. Decreased intercondylar notch width in the DH animals indicates that bone remodeling at the ACL insertion site is a response to elevated ACL laxity.

Animals↗
PubMed2006

Clinical study of hereditary disorders of connective tissues in a Chilean population: joint hypermobility syndrome and vascular Ehlers-Danlos syndrome.

OBJECTIVE: To demonstrate the high frequency and lack of diagnosis of joint hypermobility syndrome (JHS) and the seriousness of vascular Ehlers-Danlos syndrome (VEDS). METHODS: Two hundred forty-nine Chilean patients with hereditary disorders of the connective tissues (CTDs) and 64 control subjects were evaluated for the diagnoses of JHS and VEDS using the validated Brighton criteria, as compared with the traditional Beighton score. In addition, the presence of blue sclera was determined, with the degree of intensity graded as mild, moderate, or marked. RESULTS: The frequency of hereditary CTDs was 35%, with diagnoses of JHS in 92.4% of subjects, VEDS in 7.2%, and osteogenesis imperfecta in 0.4%. The Beighton score proved to be insufficient for the diagnosis of JHS (35% of subjects had a negative score), whereas the Brighton criteria yielded positive findings (a diagnosis of JHS) in 39% of control subjects. Blue sclera was frequent, being identified in 97% of JHS patients and 94% of VEDS patients. Moderate osteopenia/osteoporosis was observed in 50% of patients with VEDS and 26% of those with JHS. Dysautonomia, dyslipidemia, and scoliosis were more frequent in VEDS patients than in JHS patients. The typical JHS facial appearance and the "hand holding the head sign" were identified. Raynaud's phenomenon was extremely rare in JHS patients (2%). Ruptured uterus and cerebral aneurysm occurred in 12% and 6% of VEDS patients, respectively. Spontaneous pneumothorax was more frequent in VEDS patients (11%) than in JHS patients (0.9%). CONCLUSION: JHS is very frequent but usually undiagnosed. The Beighton score is an insufficient method for JHS diagnosis. We recommend that physicians learn to recognize the typical facial features of JHS and be able to identify blue sclera. We also propose that validated hypermobility criteria be routinely used. Further research is needed to determine why the prevalence of JHS is so high in Chile.

Adolescent↗
PubMed1992

Effect of tension and placement of a prosthetic anterior cruciate ligament on the anteroposterior laxity of the knee.

We wished to determine the optimal tension required to restore normal joint laxity to anterior cruciate ligament (ACL)-deficient knees using a braided polyethylene ACL prosthesis (PACL). In 10 cadaveric specimens, we measured the anteroposterior (AP) laxity of the intact knee at 10 degrees, 30 degrees, 60 degrees, and 90 degrees of flexion. The ACL was then removed and replaced with the PACL using tunnel-tunnel (T-T) and "over-the-top" (OTT) placement techniques. In both positions, the PACL was initially tensioned to 0, 9, 18, and 27 N with the knee flexed to 30 degrees. AP joint laxity was then measured at each flexion angle. With an increase in initial tension, there was a corresponding decrease in AP laxity. At 30 degrees and 90 degrees of flexion, AP laxity was not significantly different from normal using T-T placement and an initial tension of 0 N. At 90 degrees of flexion, AP laxity was not significantly different from normal using OTT placement at 0 or 9 N of initial tension. For both positions, all other tension levels and flexion angles constrained AP laxity. No laxity differences were detected between the OTT and T-T positions at any flexion angle. The variability in AP laxity of the T-T position was significantly greater than OTT. With a 150-N anterior shear force applied to the proximal tibia, the maximum tensions developed in the PACL were not significantly different between the two positions except at 90 degrees. The results suggest that implantation of the PACL is best performed using OTT positioning with an initial tension of 0 N applied at 30 degrees of knee flexion.

Adult↗
PubMed1992

Tissue ingrowth into titanium and hydroxyapatite-coated implants during stable and unstable mechanical conditions.

Lack of initial mechanical stability of cementless prostheses may be responsible for fibrous tissue fixation of prosthetic components to bone. To study the influence of micromovements on bony ingrowth into titanium alloy (Ti) and hydroxyapatite (HA)-coated implants, a loaded unstable device producing movements of 500 microns during each gait cycle was developed. Mechanically stable implants served as controls. The implants were inserted into the weight-bearing regions of all four femoral condyles in each of seven mature dogs. Histological analysis after 4 weeks of implantation showed a fibrous tissue membrane surrounding both Ti and HA-coated implants subjected to micromovements, whereas variable amounts of bony ingrowth were obtained in mechanically stable implants. The pushout test showed that the shear strength of unstable Ti and HA implants was significantly reduced as compared with the corresponding mechanically stable implants (p less than 0.01). However, shear strength values of unstable HA-coated implants were significantly greater than those of unstable Ti implants (p less than 0.01) and comparable to those of stable Ti implants. The greatest shear strength was obtained with stable HA-coated implants, which was threefold stronger as compared with the stable Ti implants (p less than 0.001). Quantitative determination of bony ingrowth agreed with the mechanical test except for the stronger anchorage of unstable HA implants as compared with unstable Ti implants, where no difference in bony ingrowth was found. Unstable HA-coated implants were surrounded by a fibrous membrane containing islands of fibrocartilage with higher collagen concentration, whereas fibrous connective tissue with lower collagen concentration was predominant around unstable Ti implants. In conclusion, micromovements between bone and implant inhibited bony ingrowth and led to the development of a fibrous membrane. The presence of fibrocartilage and a higher collagen concentration in the fibrous membrane may be responsible for the increased shear strength of unstable HA implants. Mechanically stable implants with HA coating had the strongest anchorage and the greatest amount of bony ingrowth.

Analysis of Variance↗