Subchondral Defects Research Articles

EXPERIMENTAL TIBIAL PLATEAU FRACTURES AUGMENTED WITH CALCIUM PHOSPHATE CEMENT OR AUTOLOGOUS BONE GRAFT

Depression fractures of the tibial plateau are often managed with use of internal fixation and autologous bone-grafting to maintain an anatomical reduction. Bone-grafting, however, provides only limited stability. As calcium phosphate cements have appropriate mechanical properties, they may provide a more suitable alternative. The objective of this study was to compare the effect of a calcium phosphate cement with that of impacted cancellous autograft for maintaining an anatomical reduction in an experimental model of a tibial plateau fracture. Standardized cylindrical subchondral defects that were 8 mm in diameter and 10 mm deep were created bilaterally beneath the subchondral bone of the articular cartilage in the lateral tibial plateau of goats. An osteotome was used to fracture the overlying subchondral plate and articular cartilage. The plateau fracture fragment was completely depressed into the subchondral defect and then was anatomically reduced. The defects were randomly filled with either calcium phosphate cement or cancellous autograft. No internal fixation was used. The tibiae were harvested at varying time-periods that ranged from twenty-four hours to eighteen months. The stiffness of the healing augmented plateau fractures was determined. Histological specimens were assigned a score for degenerative changes. Loss of anatomic reduction was demonstrated in photomicrographs, and the amount of subsidence of the osteochondral fragment was measured in whole-mount histological sections. The prevalence and degree of fracture subsidence was significantly reduced at all time-points in the defects treated with calcium phosphate cement compared with those filled with autograft (p < 0.05). There were no significant differences in fracture stiffness between the two treatment groups at any of the time-points examined. The calcium phosphate cement was rapidly resorbed, and the volume fraction of the calcium phosphate cement was decreased to 4% at six months. The trabecular bone volume in the defects was restored to that of the intact controls at six months in both treatment groups. Cancellous autograft did not maintain an anatomical reduction of the tibial plateau fractures in this model. In contrast, augmentation with calcium phosphate cement prevented subsidence of the fracture fragment and maintained articular congruency as the fracture healed. The improved articular congruency reduced the prevalence and severity of degenerative changes in the joint.

The stubborn hip: Idiopathic avascular necrosis of the hip

Objective: To highlight the unusually indolent course of avascular necrosis in this patient, the risk factors of which chiropractors should be aware, the necessity of and means to an early diagnosis, the limitations of plain film radiographs, as well as the current medical treatments. Clinical Features: A 27-year-old male professional soccer player had a tight and achy right hip for approximately 6 years, a condition that increased with physical activity. His active range of motion was limited by 25% in extension and abduction, and all resisted ranges of motion produced pain. After an equivocal radiograph and bone scan, magnetic resonance imaging revealed a subchondral defect located on the superior aspect of the right femoral head, consistent with avascular necrosis of the femoral head. Intervention and Outcome: Presurgical management included Cybex testing, massage, myofascial release, interferential current, muscle strengthening, and muscle balancing exercises 3-5 times per week for 5 months. The patient underwent a curette procedure. Six weeks later, he returned to the chiropractic office for postsurgical rehabilitation, in which he is still involved today. He has made progress with respect to flexibility, strength, and muscle coordination. Conclusions: Idiopathic avascular necrosis of the hip is a clinical entity characterized by pain in the hip made worse with activity and at night, which may radiate to the groin, back, or thigh. Often, physical exam and radiographic findings are equivocal, at which point advanced imaging such as magnetic resonance imaging should be ordered to identify the disease in its earliest stages. (J Manipulative Physiol Ther 2003;26:e11)

Rapidly destructive osteoarthritis of the hip: MR imaging findings.

The aim of our study was to describe the MR imaging findings in patients with rapidly destructive osteoarthritis of the hip. The key MR imaging features of rapidly destructive hip osteoarthritis include joint effusion (100%), bone marrow edemalike pattern in the femoral head and neck (100%) or acetabulum (83%) or both, femoral head flattening (92%), and cystlike subchondral defects (83%). Additional findings are low-signal-intensity lines (33%) in the femoral epiphysis, bandlike areas of low signal intensity in the upper pole of the femoral head (8%), and focal signal abnormalities in the adjacent soft tissues (33%) on short tau inversion recovery MR images, fat-suppressed T2-weighted MR images, and fat-suppressed gadolinium-enhanced T1-weighted MR images.

Epidural anaesthesia for arthroscopic knee surgery in a patient with Takayasu's arteritis

Epidural anaesthesia for arthroscopic knee surgery in a patient with Takayasu's arteritis

Defect Reconstruction in Articular Calcaneus Fractures with a Novel Calcium Phosphate Cement

Background: Major osseous defects in trauma or tumor patients require surgical reconstruction. While transplantation of autogenous or allogenous bone is still regarded as the standard, a multitude of alternative substitute materials has been developed in the recent years. Currently, the majority of commercially available products is based on calcium phospate minerals which are known to be osteoconductive, but in which resorption occurs slowly, if at all. A new class of calcium phosphate cements has recently been introduced that may offer better resorbability due to their nanocrystalline structure. Patients and Methods: In a prospective study of eleven patients with twelve joint depression calcaneal fractures requiring open reduction and internal stabilization, the subchondral defects were filled with a novel nanocrystalline calcium phosphate cement (Biobon®). Nine patients with ten fractures underwent a 1-year clinical and radiologic follow-up. Results: The postoperative course was uneventful except for one postoperative infection. On follow-up X-rays, the contours of the cement material became blurred and its size decreased. Biopsies taken after 6–8 months during plate removal demonstrated residual cement with intense osseointegration. Signs of inflammatory tissue response were absent, and part of the material had been replaced by new bone. Conclusions: The substitute material investigated in this study has a high biocompatibility and may represent an interesting alternative to bone grafts. Compared to sintered calcium phosphates, the resorbability of the new cement appears superior due to its nanocrystalline structure. The low compressive strength, however, does not permit early weight bearing and requires additional stabilization with osteosynthetic implants.

KNEE INJURY-BASKETBALL

HISTORY: A 13 year old freshman basketball player stopped suddenly in the game and turned on his right knee. Immediately, he felt a pinch in the anterior knee but was able to continue the game. Next morning, he woke up with swelling in his right knee. He presented to the Emergency Room with a diffusely tender right knee with a positive McMurray's test. He was told he had a normal xray and that he had torn a meniscus. He then was given an appointment to the sports medicine clinic two weeks later. PHYSICAL EXAMINATION: In the sports clinic, an examination revealed a moderate effusion, range of motion of 2 to 130 degrees, tenderness at the inferior pole of the patella with resisted extension, no extensor lag, and no joint line tenderness. DIFFERENTIAL DIAGNOSIS: Avulsion fracture of the inferior pole of the patell Sindig-Larsen-Johanssen disease Bipartite patella Oagood Schlatter's disease TESTS AND RESULTS: Emergency Room Radiographs Knee anterior-posterior and lateral radiographs: small subchondral defect of the lower half of the articular aspect of the patella with loose bone fragment associated suggestive of osteochondritis dissecans per radiology reprot. Sports Medicine Clinic Radiographs Knee anterior-posterior, lateral, tunnel, sunrise radiographs: patellar avulsion fracture displaced posteriorly 2mm. FINAL/WORKING DIAGNOSIS: Sleeve fracture of the inferior patella TREATMENT AND OUTCOMES: Patient was placed in a knee immobilizer and referred to orthopedics. Repeat exam one week later by consultant showed a persistent effusion, tenderness at the superior patellar tendon, and an extensor lag of 15 degrees. MRI is order. MRI shows an osteochondral fracture of the posterior surface of the inferior pole of the patella with fracture fragment displaced posteriorly into the retropatellar joint space. Conservative treatment is continued. 2nd opinion from another orthopedic consultant was obtained. His exam showed mild effusion, patellofemoral clunk, and no extensor lag. Options of arthroscopy vs. observation were discussed with the patient and mother. After the discussion, the family decided on observation. Patient is to follow up in 6 weeks with repeat knee xrays and exam.

Subchondral defects in caprine femora augmented with in situ setting hydroxyapatite cement, polymethylmethacrylate, or autogenous bone graft: biomechanical and histomorphological analysis after two-years

Juxta-articular defects pose significant challenges due to the high risk of fracture of the subchondral plate and articular cartilage. We evaluated the mechanical and histomorphological repair process of caprine subchondral femoral defects augmented with either a bioresorbable in situ setting hydroxyapatite cement (HAC), polymethylmethacrylate (PMMA), autogenous bone graft (AG), or left empty. Twelve-mm subchondral defects were made bilaterally in the medial femoral condyles of skeletally mature goats and augmented with a test material or left empty. Femurs were harvested at varying time periods out to 2 years and evaluated for subchondral stiffness and histomorphological indices. Several defects augmented using autograft or left empty sustained focal fracture of the subchondral plate. No HAC or PMMA augmented defects showed evidence of subchondral fracture. The HAC and PMMA augmented defects showed comparable stiffness at all time points. The mean volume fraction of HAC remaining within the defects progressively decreased from 96% at 24 h to 38% at 2 years. The new bone replacing the HAC appeared to have normal physiological architecture and orientation. In situ setting hydroxyapatite cement may be a viable alternative for the repair of subchondral defects with an important advantage that while undergoing gradual resorption and replacement with host bone, mechanical integrity of the skeletal defect is maintained.

Use of recombinant human osteogenic protein-1 for the repair of subchondral defects in articular cartilage in goats.

The objective of this pilot study was to examine in vivo the potential of recombinant human osteogenic protein-1 (rhOP-1, also called bone morphogenetic protein-7, BMP-7) for treatment of subchondral lesions by induction of new hyaline cartilage formation. Subchondral left knee defects in 17 mature goats were treated with fresh coagulated blood mixed with (1) rhOP-1 combined with collagen (OP-1 device, 400 microgram/mL); (2) rhOP-1 alone (OP-1 peptide, 200 microgram/mL); (3) OP-1 device with small particles of autologous ear perichondrium; (4) OP-1 peptide with small particles of autologous ear perichondrium; or (5) autologous ear perichondrium alone (controls). rhOP-1 was combined with either collagen (OP-1 device) or not (OP-1 peptide). The defects were closed with a periosteal flap. The formation of cartilage tissue was studied by histologic and biochemical evaluation at 1, 2, and 4 months after implantation. One and 2 months after implantation there were no obvious differences between control and rhOP-1-treated defects. Four months after implantation, only one out of three controls (without rhOP-1) showed beginning signs of cartilage formation while all four rhOP-1-treated defects were completely or partly filled with cartilage. A significant linear relationship was found between rhOP-1 concentration and the total amount of aggrecan in the defects. These results suggest that implantation of rhOP-1 promotes cartilage formation in subchondral defects in goats at 4 months after implantation. Therefore, rhOP-1 could be a novel factor for regeneration of cartilage in articular cartilage defects.

Current status and perspectives of shoulder replacement

Basis of the modern shoulder implants is the Neer II-system, a non constrained total shoulder prosthesis with conforming radii of curvature and improved protection against dislocation. The second generation of shoulder prosthesis is based on the geometric shaft design of the Neer II prosthesis and offers not only a variety of modular head- and shaft-sizes but also through different radii a physiologic rotation-translation-mechanism. The third generation of humeral head prosthesis carries the concept of an anatomic reconstruction one step further and enables the surgeon to adjust the inclination and the eccentric offset of the humeral head to restore the centre of rotation. The latest development in shoulder arthroplasty are humeral head prosthesis with a fully variable 3-dimensional modularity to independently adjust the prosthetic head position regardless of the individual shaft geometry. This achieves a 3-dimensional adaptability of the prosthetic head about the stem axis in the coronary and in the sagittal plane. Besides of the humeral shaft prosthesis an alternative concept of shoulder joint replacement is established - the replacement of the humeral head articular surface. A hemispheric surface prosthesis - cup arthroplasty - is cemented onto the residual humeral head, which eliminates the obligatory humeral head resection and the reaming of the medullary canal. Bipolar shoulder prosthesis are humeral shaft prosthesis with a bi-rotational head system. Their indication is limited to pre-existing lesions of the rotator cuff and/or the glenoid surface. The inverse total shoulder prosthesis reverses the articular surface morphology of the humeral head and the glenoid. The hemispheric glenoid component serves as the centre of rotation for the concave epiphyseal proximal humerus component. This implant is especially used in cases of massive rotator cuff deficiencies. The role of shoulder prosthesis in treating acute humeral head fractures needs special consideration. A fracture prosthesis has to restore the exact length of the humerus, the centre of rotation, and the anatomical retroversion. Positioning of the tubercula and their adequate osteosynthesis is most critical and fundamental to ensure a correct healing process. A failed consolidation of the tubercula does not lead to a satisfying result. The shoulder joint replacement can be sufficiently fixated in cemented, cementless or hybrid techniques. Today several component design variations of cemented glenoid implants exist. Their main distinction is the fixation system which can be divided into two main groups - the keel - and the peg-shaped glenoid components. The peg-shaped anchorage system shall guarantee a greater stability against shear-forces. Cementless glenoid components consist of a polyethylene inlay and a surface treated metal-back with an integrated fixation system. These fixation systems are object of intensive biomechanical research and range from conventional screw fixation to specialised cone systems and self-cutting cage-screw-systems. The critical area of cementless glenoid components is the transition zone of the PE-inlay and the metal-back because of high force development. The question of implanting a hemi- or total shoulder prosthesis is answered by the morphologic changes of the glenoid articular surface, which includes the size of the subchondral defect and the underlying etiology of the shoulder joint disease, and the age of the patient. Preoperative planning must consist of an adequate radiologic work-up - X-ray, CT or MRI - to accurately assess the glenoid morphology. G. Walch categorised the different glenoid lesions and developed a very important classification of possible glenoid deformations. To compare and evaluate the operative results one must consider the different shoulder prosthesis and the discrepancies between a hemi- and a total shoulder prosthetic replacement. Looking at the loosening and survival rate of the implant the results are

Intraosseous ganglion of the trapezoid

The term intraosseous ganglion has been used to describe cystic subchondral defects of bone derived independently of joint pathology. Case reports have most often dealt with the lower extremity, with a much less frequent occurrence reported within the carpal bones. This is a case of an intraosseous ganglion occurring within the trapezoid. Case Report A 44-year-old left-handed male loading dock laborer presented with a 3-month history of intermittent left hand pain exacerbated by power grip. He had no history of trauma or inflammatory disease. On physical examination moderate diffuse swelling and tenderness over the dorsal radial aspect of the left wrist was found. The first carpometacarpal joint grind test was strongly positive. Motion at the left wrist or thumb was not limited. Pinch and grip strengths were diminished. Laboratory studies were within normal limits. Plain x-ray films of the left wrist showed marked cortical sclerosis of the trapezoid. A central lucency was present but difficult to assess against the dense surrounding bone (Fig. I). Arthritic changes were not present. The bone scan had a normal radionuelide angiogram and increased uptake in the region of the left trapezoid in the early (Sminute) and late (4-hour) phases (Fig. 2). Computed tomography demonstrated cortical thickening and a central lu

Evaluation of subchondral lesion size in osteochondrosis of the scapulohumeral joint in dogs

Summary In 62 dogs, the size of 104 subchondral osteochondrosis lesions, expressed as a percentage of the width of the humeral head (the length of the axis from the intertubercular groove to the edge of the humeral head), was significantly (P &lt; 0.0001) different in joints with intact vs ruptured articular cartilage and in joints associated with vs without clinical signs. The status of the articular cartilage covering the subchondral defect was evaluated by use of positive-contrast arthrography.

Successful arthroscopic treatment of shoulder osteochondrosis in the dog

ABSTRACTFourteen shoulder joints in 12 dogs were treated arthroscopically for osteochondrosis. The arthroscopic procedure included removal of all osteochondral flaps and curettage of the edges of the subchondral defect. Histological examination of biopsy samples from eight joints revealed synovitis in all cases. Arthroscopic surgery of shoulder osteochondrosis in the dog proved to be a less time consuming procedure than arthrotomy with minimal soft tissue trauma and allowed a rapid return to function of the patients.

Comparison of the diagnostic accuracy of positive-contrast arthrography and arthrotomy in evaluation of osteochondrosis lesions in the scapulohumeral joint in dogs

Summary During a 6-year-period (1985-1991), 120 positive-contrast arthrograms were made in 70 dogs to evaluate osteochondrosis lesions in the scapulohumeral joint. In 76 shoulders, the arthrographic findings were compared with surgical or histopathologic findings to evaluate the accuracy of the arthrographic technique. Positive-contrast arthrography was found to be accurate in evaluation of the status of the articular cartilage. In revealing discontinuity of the articular cartilage, the results of arthrography were false-negative in 4 shoulders (58/66; accuracy, 88%). In detecting thick cartilage covering a subchondral defect, the results of positive-contrast arthrography were false-positive in 4 joints (6/11; accuracy, 55%). In detecting fragmentation of the cartilage, arthrography provided false-negative results in 4 joints (7/11; accuracy, 64%). This technique enabled detection of joint mice, especially within the bicipital tendon sheath (no false-positive results). Arthrography failed to reveal joint mice within the caudal pouch in 2 joints (15/17; accuracy, 88%). Joint effusion also could be evaluated and was correlated with synovitis, degenerative joint disease, and loose or detached cartilage flaps. Postarthrography complications were not observed with this technique.

ULTRASONOGRAPHY OF THE EQUINE STIFLE

Ten stifles from 5 clinically sound adult horses were scanned by high‐resolution ultrasound. Normal anatomic structures seen consistently included the subcutaneous tissue, the medial, middle and lateral patellar ligaments, the medial and lateral collateral ligaments, the femoral trochlear ridges, and menisci. Cruciate ligaments could not be visualized in the standing horse. Four stifle specimens obtained from 2 of these normal horses at necropsy were scanned in a water bath to create optimal technical conditions. The sonographic appearance of stifle specimens was similar to that found in live horses. Results from ultrasonographic examination of 3 horses with stifle abnormalities were described to illustrate some applications of ultrasonography in the evaluation of the equine stifle. In these horses, ultrasound was a valuable diagnostic tool to study joint effusion, synovial thickening, articular cartilaginous and subchondral defects, and soft tissue/bony injuries.

Evaluation of the prognostic value of positive-contrast shoulder arthrography for bilateral osteochondrosis lesions in dogs

SUMMARY To investigate whether arthrographic findings had any prognostic value with respect to treatment and outcome of bilateral osteochondrosis, shoulder arthrograms (n = 80) from 40 dogs with bilateral lesions were evaluated. Arthrography was performed, using 1.5 to 4 ml of a 25% solution of meglumine-sodium diatrizoate, with admixture of 0.2 mg of epinephrine. A shoulder with signs of pain and lameness was surgically treated. The contralateral shoulder was treated conservatively, and the final outcome was compared with the arthrographic findings. In 37 dogs, signs of lameness and pain were associated with a loose cartilage flap and, in 3, with a detached cartilage flap. In 2 dogs, admitted with bilateral lameness, a loose cartilage flap was detected in both shoulders. Of 12 dogs with a detectable loose cartilage flap in the contralateral shoulder joint, 6 became lame 2 to 4 months after initial surgical intervention and needed bilateral surgery. In the contralateral joint, development of thick articular cartilage over the subchondral defect or a detached cartilage flap lodged in the caudal pouch of the shoulder joint was a favorable prognostic sign. Such dogs had no signs of lameness on the contralateral side during a follow-up period that ranged from 1 to 7 years.

Osteochondral fragmentation of the distal aspect of the patella in horses

A condition characterised by osteochondral fragmentation of the distal aspect of the patella in 15 horses is described. The problem was unilateral in six horses and bilateral in nine. There were eight Quarterhorses, three Thoroughbreds, two American Saddlebreds, one American Paint and one Warmblood-Thoroughbred cross. A previous medial patellar desmotomy had been performed on 12 of the 15 horses. The condition manifested as hindlimb lameness and stiffness ranging from mild to severe. There was fibrous thickening in the stifle area in the 12 cases with a previous medial patellar desmotomy, and synovial effusion in seven of 12 cases. Synovial effusion was present in two of the three cases in which a previous medial patellar desmotomy was not performed. The radiographic changes included bony fragmentation, spurring (with or without an associated subchondral defect), subchondral roughening and subchondral lysis of the distal aspect of the patella. All horses were treated with arthroscopic surgery. The lesions at arthroscopy varied from flaking, fissuring, undermining or fragmentation of the articular cartilage to fragmentation or lysis of the bone at the distal aspect of the patella. The subchondral bone was involved in all cases that had a previous medial patellar desmotomy. Of the 12 horses that had a previous medial patellar desmotomy, eight became sound at their intended use, one was sold in training without problems, one is in early training without problems, one never improved and one is in convalescence. Of the three that did not have a patellar desmotomy, two performed their intended use well but one was unsatisfactory.

Arthrography of the equine shoulder joint

Techniques and normal radiographic anatomy for positive and double contrast shoulder arthrography in horses were evaluated. General anaesthesia was used for most radiographic projections of the shoulder. The mediolateral projection provided the most information during arthrography, although the supinated mediolateral view occasionally allowed better definition of the cartilage surfaces on the medial aspects of the humeral head. The craniocaudal mediolateral oblique and caudocranial projections provided limited additional information. Water soluble non-ionic contrast agents, such as metrizamide and iohexol, were suitable for shoulder arthrography; iohexol resulted in less synovitis and lameness. Arthrography in cases of osteochondrosis and osteochondritis dissecans allowed better evaluation of cartilage attachment to subchondral bone, better evaluation of the length and depth of cartilage lesions and more accurately defined the site and shape of osteocartilaginous free bodies. Cartilage thickening without detachment from the subchondral bone could only be determined by arthrography. Although these thick cartilage regions may later dissect from the subchondral bone, most cases where the cartilage was firmly adherent were not candidates for surgical debridement and carried a favourable prognosis. The determination of a free flap by arthrography indicated the need for surgery. Extensive humeral and glenoid cavity lesions were better defined by arthrography, allowing a rational decision between surgical debridement or euthanasia. Using arthrography, evaluation of the size and patency of the communicating canal to a subchondral cystic defect better separated cases with long, narrow and poorly patent canals for conservative rather than surgical therapy.

Arthroscopic treatment of osteochondritis dissecans in the canine shoulder.

Twenty-three shoulders of 21 dogs were treated arthroscopically for osteochondritis dissecans (OCD). Thirteen dogs had bilateral lesions detectable radiographically; however, only two dogs had arthroscopic surgery on both shoulders. Arthroscopic procedures included removal of the osteochondral flap, curettage of the subchondral defect, and partial synovectomy. Fourteen dogs were using the treated limb within 1 day and eight dogs within 2 days, although some lameness may have persisted for several weeks. Force plate evaluation was effective for comparison of preoperative and postoperative mean peak force/body weight (PF/BW) values. Improvement was detected objectively in 9 of the 10 dogs returned for postoperative force plate analysis. All owners were satisfied with the cosmetic results and the rapid return to function.

Abnormalities in the axial skeleton of broiler breeding fowl

The spinal region containing caudal notarium, free thoracic vertebra (T6), and cranial synsacrum was collected from 27 male broiler breeding fowl which were about 60 weeks old when killed. In 12 birds minor abnormalities were detected on gross morphological examination, with minimal scoliotic curvature being the most frequent finding. Particular attention was paid to articulations. Radiological and histopathological examination revealed subchondral defects due to articular osteochondrosis in every spine examined. Such lesions must represent the sequelae of disturbed endochondral ossification in younger birds. Many lesions were severe, showed little evidence of repair and contained clefts and marked cartilage necrosis. Clefts were not always associated with osteochondrosis but were also observed in slightly thickened articular cartilage and that judged to be of normal thickness. In this instance clefts occurred in deep regions of articular cartilage at sites which frequently showed chondrocyte and matrix change. The latter are likely to be the primary lesions. It also seems probable that the same anatomical sites are predisposed to cell death/clefts and osteochondrosis. Clefts in adult articular cartilage, unrelated to lesions of osteochondrosis, are more likely to be progressive leading to segmental cartilage detachment and destructive cartilage thinning.

Subchondral pathways to the superior surface of the human talus.

The suggestion that the blood supply to subchondral bone plays an active role in the nutrition of adult articular cartilage is a source of controversy. Morphological confirmation of the presence of subchondral defects extending through the basal cartilage layer of the adult human talus is presented. Perfusion of a fluorescent dye through these breaks offers the possibility that they may serve as active pathways for the transport of nutrients to the cartilage. The distribution patterns of the defects in areas of intermittent cartilage loading is noted and its significance is discussed.