Effects of a surface matching articular resurfacing device on tibiofemoral contact pressure: results from continuous dynamic flexion-extension cycles

Introduction  

The application of a defect-size metal implant for the treatment of focal articular cartilage lesions of the femoral condyle is of potential concern resulting in cartilage damage to opposing biological structures. This in vitro study aims to determine the tibiofemoral contact pressure with a contoured articular partial femoral resurfacing device under continuous dynamic pressure loads.     

Soft tissue balance using the tibia first gap technique with navigation system in cruciate-retaining total knee arthroplasty

Purpose  

The procedures of bone cut and soft tissue balancing in total knee arthroplasty (TKA) are usually performed using the measured resection technique or the gap technique; however, the superiority of these techniques is controversial. An increase of extension gap after resection of the femoral posterior condyle and a difference between gaps before and after femoral component placement have been reported. We therefore postulated that the use of the tibia first gap technique might have an advantage in avoiding the mismatch before and after resection of the femoral posterior condyle and femoral component placement.     

Internal rotation of the tibial component is frequent in stiff total knee arthroplasty

Background  

Stiffness complicating TKA is a complex and multifactorial problem. We suspected internally rotated components compromised motion because of pain, patellar maltracking, a tight medial flexion gap, and limited femoral rollback on a conforming lateral tibial condyle.     

Anterior cruciate ligament reconstruction with the semitendinosus tendon in children

Objectives  

Reconstruction of the anterior cruciate ligament in children without creating permanent damage to the tibial or femoral physes. The semitendinosus tendon, left attached distally, is passed through a tunnel in the tibial epiphysis, led through the joint, passed behind the lateral femoral condyle and fixed to the outer aspect of the femur with a staple.     

Factors associated with acute articular cartilage lesions of the patella and lateral femoral condyle in acute first-time lateral patellar dislocation: A prospective magnetic resonance imaging study

ObjectivesTo identify risk factors of acute articular cartilage lesions of the patella and lateral femoral condyle in acute first-time lateral patellar dislocation (LPD).MethodsMagnetic resonance images were prospectively analyzed in 115 patients in an acute first-time LPD. Factors included gender, skeletal maturity, trochlear dysplasia, patellar height, and tibial tuberosity–trochlear groove (TT-TG) distance. Binary logistic regression analysis was carried out to identify the independent risk factors for the incidence of acute articular cartilage lesions of the patella and lateral femoral condyle in acute first-time LPD.ResultsThe incidence of acute articular cartilage lesion of the patella and lateral femoral condyle were 46.1% and 27% in acute first-time LPD, respectively. Univariate analysis revealed significantly higher incidence rate of acute articular cartilage lesion of the patella in male (P = 0.027), skeletally mature (P = 0.035), normal TT-TG distance (P = 0.043) and normal femoral trochlea (P = 0.031). Risk factors for the incidence of acute articular cartilage lesion of the patella were skeletally mature (odds ratio (OR): 2.324), normal TT-TG distance (OR: 2.824) and normal femoral trochlea (OR: 3.835). Univariate analysis revealed significantly higher incidence rate of acute articular cartilage lesion of the lateral femoral condyle in skeletally mature (P = 0.027) and normal femoral trochlea (P = 0.031). Risk factor for the incidence of acute articular cartilage lesion of the lateral femoral condyle was normal femoral trochlea (OR: 3.347).ConclusionsFor patients in acute first-time LPD, compared with other parameters, the normal femoral trochlea, normal TT-TG distance and skeletally mature are independent risk factors for the incidence of acute articular cartilage lesion of the patella, and the normal femoral trochlea is an independent risk factor for the incidence of acute articular cartilage lesion of the lateral femoral condyle.     

Treatment of osteonecrosis in the knee joint of a rabbit using autologous cultured osteoblasts

Backgound

To develop a successful treatment modality for osteonecrosis, an appropriate animal model is essential. We have proposed a new osteonecrosis model that shows the total amount of necrosis and in which we observed new bone formation after transplanting autologous cultured osteoblasts.

Materials and methods

The femoral condyles of the right knees of New Zealand white rabbits were exposed after dissecting the ligaments surrounding the distal femur. After which, the metaphyseal–diaphyseal junction was cut using a saw, and the entire femoral condyle was isolated. After three liquid nitrogen treatments, the isolated femoral condyle was internally fixated to the femoral shaft using two or three Kirschner wires. Bone marrow isolated from the iliac crest was cultivated to differentiate it into osteoblasts, and the cultured cells were then injected into the necrotic bone.

Results

Viable osteocytes with well-stained nuclei were not present in the necrotic areas at any stage of the development of the osteonecrosis model within 24 wk after osteonecrosis induction. However, new bone formation with osteocytes and blood vessels was observed in the necrotic bone 12 wk after transplanting the autologous cultured osteoblasts.

Conclusions

The distal femoral condyle of the rabbit is an appropriate model for demonstrating osteonecrosis and treatment evaluation owing to its easy reproducibility and treatment interpretation. Therefore, autologous cultured osteoblast treatment would seem to be a potentially successful treatment modality for osteonecrosis.     

Spontaneous hyaline cartilage regeneration can be induced in an osteochondral defect created in the femoral condyle using a novel double-network hydrogel

Background  

Functional repair of articular osteochondral defects remains a major challenge not only in the field of knee surgery but also in tissue regeneration medicine. The purpose is to clarify whether the spontaneous hyaline cartilage regeneration can be induced in a large osteochondral defect created in the femoral condyle by means of implanting a novel double-network (DN) gel at the bottom of the defect.     

Reconstruction of scaphoid non-union and total scaphoid avascular necrosis in a pediatric patient: a case report

Background

The medial femoral condyle vascularized bone graft has grown in popularity for treating recalcitrant fracture non-unions and has become particularly useful in treating scaphoid non-union with avascular necrosis of the proximal pole. The medial femoral condyle is an excellent source of dense, well-vascularized bone and results in minimal donor site morbidity.

Methods

We describe an unusual case of chronic scaphoid non-union and total scaphoid avascular necrosis in a skeletally immature patient. Scaphoid reconstruction was performed with a vascularized medial femoral condyle graft, with successful graft incorporation, and restoration of pain-free wrist motion.

Conclusions

Technical considerations for harvest of the medial femoral condyle bone graft in the skeletally immature patient are discussed.     

Posteriorly inserted anterior cruciate ligament in knees with discoid lateral meniscus corresponding to bony morphological characteristics of femoral lateral condyle

Purpose

Discoid meniscus often causes mechanical problems and needs surgical treatment at an early age. However, many aspects of its morphological development and changes remain unknown. The purpose of this study was to investigate the insertion of the femoral anterior cruciate ligament (ACL) via the behind-ACL approach and the morphology of the lateral femoral condyle to which the ACL attaches to clarify the morphological characteristics of the knee with discoid lateral meniscus (DLM).

Allogenous bone with collagen for repair of deep osteochondral defects

Background

A scaffold for treatment of deep osteochondral defects should be stable, integrate well, and provide a surface for chondrocytes. To meet these demands, a biphasic scaffold of allogenous sterilized bone with a collagen surface was developed. Integration was tested in the sheep model.

Material and methods

Cartilage chips were taken from the nonweight-bearing area of the left knee of 12 sheep and cultured. After 4 wk a second procedure followed and defects of 9.4-mm diameter at the weight-bearing area of the medial femoral condyle of the right knee were created. The sterilized scaffold was inserted and the cultured autologous chondrocytes were dripped onto the surface. After 6 wk, 3 mo, and 6 mo the animals were sacrificed; the explanted femoral condyles were evaluated macroscopically and using histologic, immunohistochemical, and electronmicroscopic methods.

Results

After 6 wk the level of the surface was well preserved, after 3 mo parts of the scaffold were sintered but after 6 mo the surface was continuous. Full integration of the allogenous bone could be observed after 6 mo. The surface of the scaffold after 6 wk consisted of bone, but after 3 mo some chondrocytes and after 6 mo a continuous chondral layer could be detected.

Conclusions

The biphasic scaffold of allogenous bone and collagen proved to be stable and sufficiently integrated in the short- and midterm interval. Whether the chondrocytes on the surface had been derived from implanted chondrocytes or the scaffold with its surface was sufficiently chondroconductive must be answered in further investigations.     

Comparison of tunnel locations of double bundle ACL reconstruction using the conventional transtibial technique with anatomic tunnel locations using a 3D CT model

Introduction

The purposes of this study were: (1) to compare tunnel locations using the conventional transtibial technique with reference data, and (2) to identify factors that make it difficult to position the femoral tunnel correctly or contribute to breakage of the bone bridge between the two tibial tunnels.

Materials and methods

A prospective study was performed on 28 patients who underwent double bundle ACL reconstruction. Locations of each tunnel were determined using an anatomic coordinate axes method (ACAM). Measurements included: thickness of the bone bridge between tibial two tunnels (BB), height from the union (HU) point to expected joint surface, the ratio between the length of Blumensaat’s line and the anterior–posterior length of the lateral femoral condyle (RBL), and the ratio between anterior–posterior and proximal–distal lengths of the medial wall of the lateral femoral condyle (RAPPD).

Results

The posterior–anterior direction of femoral AM tunnel, the proximal–distal direction of femoral PL tunnel, and the posterior–anterior direction of femoral PL tunnel were statistically significantly different from the reference data. In correlation analyses between BB or HU and other variables, the AM tibial tunnel and RBL showed a moderate negative correlation. The cutoff point for tunnel breakage was an RLB of 1.14, meaning that the possibility of bone bridge breakage would increases for RBL values of >1.14.

Conclusions

It seems that conventional transtibial drilling technique used during double bundle ACL reconstruction does not reproduce correct tunnel locations compared with reference data. This problem was found to be related to the bony geometry of the medial wall of the lateral femoral condyle or the bone bridge between the two tibial tunnels. Our results indicate that RBL should be determined by pre-operative CT or plain lateral radiography, and that transtibial single bundle reconstruction or double bundle reconstruction using other methods should be attempted when the RBL exceeds 1.14.     

Bone formation within the articular cartilage of the lateral compartment of varus osteoarthritic knees

Background

One of the causes of failure after unicompartmental knee arthroplasty (UKA) for varus osteoarthritis is the progression of osteoarthritis in the lateral compartment. Bone formation within the articular cartilage has been reported as a possible cause of the deterioration of the osteoarthritis. However, its prevalence and histology are still uncertain. The purpose of the current study is to investigate bone pieces obtained from the lateral compartment of the knee during total knee arthroplasty (TKA) radiographically and histopathologically, and to examine the bone formation within the articular cartilage in detail.

Methods

Thirty-four consecutive patients, who underwent TKA for varus osteoarthritis of the knee, were included in this study. There were 6 males and 28 females and the mean age at the surgery was 74 years (range 63–85 years). Fifty-seven and 99 sagittal slabs were acquired from the resected bone pieces of the distal lateral femoral condyle and lateral tibial plateau, respectively. These slabs were investigated by soft X-ray radiographs and histopathological analyses stained with hematoxylin–eosin and elastica-Masson.

Results

On soft X-ray radiographs, bone formation (in which bone trabeculae were clearly detected) within the articular cartilage was observed in 8 (14.0 %) of 57 femoral slabs and 7 (7.1 %) of 99 tibial slabs. Histopathological analyses revealed that the bone which had formed comprised normal trabeculae and fatty marrow. There was rich vascularity in the cartilage around the formed bone.

Conclusions

The current study is the first to describe the prevalence, location, and histopathological findings of bone formation within the articular cartilage of the lateral compartment of varus osteoarthritic knees. Since the thickness of the cartilage covering the bone formation is less than that without it, it may result in the deterioration of the lateral compartment after UKA.     

Occipital condyle fractures. Prospective follow-up of 31 cases within 5 years at a level 1 trauma centre

Purpose  

Prospective investigation of incidence and outcome of occipital condyle fractures (OCF) in a level 1 trauma centre.     

In Vivo Motion of Femoral Condyles During Weight-Bearing Flexion After Anterior Cruciate Ligament Rupture Using Biplane Radiography

The purpose of this study was to investigate in vivo three- dimensional tibiofemoral kinematics and femoral condylar motion in knees with anterior cruciate ligament (ACL) deficiency during a knee bend activity. Ten patients with unilateral ACL rupture were enrolled. Both the injured and contralateral normal knees were imaged using biplane radiography at extension and at 15°, 30°, 60°, 90°, and 120° of flexion. Bilateral knees were next scanned by computed tomography, from which bilateral three-dimensional knee models were created. The in vivo tibiofemoral motion at each flexion position was reproduced through image registration using the knee models and biplane radiographs. A joint coordinate system containing the geometric center axis of the femur was used to measure the tibiofemoral motion. In ACL deficiency, the lateral femoral condyle was located significantly more posteriorly at extension and at 15° (p < 0.05), whereas the medial condylar position was changed only slightly. This constituted greater posterior translation and external rotation of the femur relative to the tibia at extension and at 15° (p < 0.05). Furthermore, ACL deficiency led to a significantly reduced extent of posterior movement of the lateral condyle during flexion from 15° to 60° (p < 0.05). Coupled with an insignificant change in the motion of the medial condyle, the femur moved less posteriorly with reduced extent of external rotation during flexion from 15° to 60° in ACL deficiency (p < 0.05). The medial- lateral and proximal-distal translations of the medial and lateral condyles and the femoral adduction-abduction rotation were insignificantly changed after ACL deficiency. The results demonstrated that ACL deficiency primarily changed the anterior-posterior motion of the lateral condyle, producing not only posterior subluxation at low flexion positions but also reduced extent of posterior movement during flexion from 15° to 60°.

Key Points

• Three-dimensional tibiofemoral kinematics and femoral condylar motion in ACL-deficient knees during upright weight-bearing flexion were measured using biplane radiography with the geometric center axis.
• ACL deficiency caused posterior subluxation of the lateral condyle with excess external femoral rotation at early flexion positions.
• On flexion from 15° to 60°, the lateral condyle moved slightly posteriorly in ACL deficiency leading to reduced extent of external femoral rotation.

Key words: anterior cruciate ligament, injury, kinematics, tibiofemoral, femoral condyle, radiography     

Validity of the Alpha Angle Measurement on Plain Radiographs in the Evaluation of Cam-type Femoroacetabular Impingement

Background  

Cam-type femoroacetabular impingement is secondary to lack of concavity at the anterosuperior femoral head-neck junction, resulting in reduced femoral head-neck offset and femoral head asphericity. This morphologic deformity can be detected by MRI and plain radiographs and quantified using the alpha angle.     

The clinical outcomes and the ability to sit straight in the Japanese style following high tibial osteotomy combined with osteochondral autologous transfer for osteonecrosis of the medial femoral condyle

Background

There have been some reports of high tibial osteotomy combined with osteochondral autograft transfer for osteonecrosis of the medial femoral condyle of the knee. However, few of them have focused on the deep knee flexion needed to sit straight in the Japanese style.

Extracorporeal shock waves in articular cartilage defects in the rats

Thirty adult Sprague–Dawley rats were used to assess the nature of healing tissues in hyaline cartilage defects and to compare the healing in defects treated with shock waves, with those in defects without treatment. A 2 × 2 mm cartilage defect with exposed cancellous bone was created in a nonweight-bearing area of each medial femoral condyle. Each right knee defect was received extracorporeal shock waves (Swiss Dolorclast) of 500 impulses in 5 min at 2 bar (comparative to 0.09 mJ/mm²), and the left knee defects were assigned as controls. The rat groups were sacrificed at 6 and 12 weeks postsurgery. Sections from each knee were stained with hematoxylin-eosin to analyze synovial adhesion, synovial thickness, bone maturation, and chondroid metaplasia and with masson trichrome to analyze collagen fiber intensity. There was not a significant difference found between the study and control groups (P > 0.05). Extracorporeal shock waves did not effect healing of the chondral defects.     

Loss of a condyle of the femur or tibia following septic arthritis in infancy: problems of management and testing of a hypothesis of pathogenesis

Purpose

The study was undertaken to: (1) describe the characteristic radiological features and problems of management of the loss of one condyle of the femur or tibia following septic arthritis of the knee in infancy and (2) test a hypothesis of the cause of the loss of a single condyle.

Methods

Radiographs of eight children with the loss of one condyle of the femur or the tibia following septic arthritis in infancy were reviewed. The course and outcome in two of these children who underwent reconstructive operations were studied. The knees of 35 stillborn foetuses were dissected to determine if the presence of synovial septae could account for the isolated loss of one condyle following infection.

Results

All eight cases showed characteristic features of loss of half the epiphysis, the underlying physis and part of the adjacent metaphysis; the other condyle was totally spared. The two children who underwent elaborate reconstructive procedures had poor outcomes at skeletal maturity, despite a series of additional operations. The foetal cadaveric study showed that complete infrapatellar synovial septae are present in some foetuses approaching 40 weeks of gestation.

Conclusions

The pattern of loss of a femoral or tibial condyle following septic arthritis is consistent with total preservation of the other condyle. The outcome of surgical reconstruction of the missing condyle is poor. The presence of a complete synovial septum could result in the localisation of infection to one half of the joint, with the destruction of one condyle.     

Der autologe Transfer der posterioren Femurkondyle bei ausgedehnten osteochondralen Schäden des Knies

Background

Large osteochondral defects of the weight-bearing zones of the femoral condyles in young and active patients were treated by autologous transfer of the posterior femoral condyle. This technique is a salvage procedure and aims at pain-free mobility of patients.

Material and methods

Between July 1999 and December 2000, 18 patients were operated on. Sixteen patients were evaluated using the Lysholm score. X-rays were done, and eight individuals underwent magnetic resonance imaging (MRI) analysis. The average age at the date of surgery was 37.4 (15–59) years, and the mean follow-up time was 55.2 (46–62) months. The mean defect size was 5.4 cm² (3.1–7.1). Trauma or osteochondrosis dissecans was pathogenetic in 81%.

Results

The Lysholm score showed a significant (p=0.001) increase from a preoperative median of 65.0 to a postoperative median of 86.0 points. Fifteen patients returned to sport activities. X-rays showed a rounding of the osteotomy edge in 12 patients and a partial bone-dense remodelling of the posterior femoral condyle in 11 patients. All MRI examinations showed vital and congruent grafts.

Conclusion

Thus, the procedure is recommended for treating large and deep focal osteochondral lesions in the weight-bearing zone of the femoral condyle.     

Operative treatment of avascular necrosis of the femoral head after slipped capital femoral epiphysis

Purpose  

The aim of the study was assessment of the medium-term outcome of operative treatment of avascular necrosis of the femoral head (ANFH) after slipped capital femoral epiphysis (SCFE).