Restoration of the Mechanical Axis in Total Knee Artrhoplasty Using Patient-Matched Technology Cutting Blocks. A Retrospective Study of 132 Cases.

BACKGROUND: The aim of this study is to evaluate the accuracy of bone cuts and the resultant alignment, using the MyKnee patient specific cutting blocks. METHODS: We retrospectively reviewed 132 patients undergoing primary TKR for osteoarthritis by one single surgeon. The operative time, the preoperative Hip-Knee-Ankle (HKA) axis based on the CT-scan, the postoperative HKA axis based on long axis standing x-rays, the planned and the actual size of the femoral and the tibial components, and the number of the recuts which has been made intraoperative were measured. RESULTS: The average preoperative HKA axis was 177.50 (range 163.50 to 1940), whereas the average postoperative HKA axis was 179.40 (range 177.10 to 182.70). No outliers were reported in the study (0%). Intraoperatively, 4 femoral components (3.03%), and 7 tibial components (5.30%) applied to the patients were different than the planned size. There was no need of recuts in any of our cases intraoperatively. CONCLUSION: The MyKnee system evaluated in this study was shown to be remarkable reliable in the coronal plane alignment, and the prediction of the component size. However, further studies are needed to determine whether there are any clinically important improvements in outcomes or patient satisfaction when using patient-specific cutting blocks for TKA.

Analysis of the Geometry of the Distal Femur and Proximal Tibia in the Osteoarthritic Knee: A 3D Reconstruction CT Scan Based Study of 449 Cases.

BACKGROUND: The aim of this study is to evaluate the geometry of the distal femur and the proximal tibia in the osteoarthritic knee using 3D reconstructive CT scan imaging. METHODS: 449 patients with knee osteoarthritis were treated surgically in our center with patient-specific technology total knee arthroplasty. Preoperatively, all the patients underwent a CT scan according to a standard protocol. Using this database, the Hip-Knee-Angle (HKA), the Femur Valgus Angle (FVA), the Tibia Varus Angle (TVA), the Posterior Tibia Slope (PTS), and the angle between the posterior condylar axis and the anatomical transepicondylar axis (PCA) for each patient were recorded and statistically evaluated. RESULTS: In overall, the mean HKA angle was 177.3±5.55, the mean FVA angle was 3.19±2.08, the mean TVA was 3.28±2.35, the PTS angle was 9.02±3.46, and the PCA angle was 2.86±0.78. Evaluation of the correlations between HKA and PCA (r=0.035), HKA and PTS (r=-0.047), and PCA and PTS (r=0.05) showed non-significant relationships (P=0.46, P=0.32, and P=0.29 respectively). No significant differences were revealed from the comparison of male patients with female patients, regarding the mean HKA, FVA, TVA, PTS, and PCA. CONCLUSION: The posterior condylar axis is a well-defined but not a reliable axis, while the transepicondylar and the anteroposterior are reliable, but not easily defined axes. Given the large ranges and standard deviations of the location of posterior condylar axis, and the important inter- and intraobserver variability in the intraoperative location of the transepicondylar and the anteroposterior axes, the use of a preoperative 3D CT scan is recommended.

Results of extra-articular subtalar arthrodesis in children with cerebral palsy.

BACKGROUND: Grice-Green extra-articular subtalar arthrodesis is considered to be a valid surgical method which improves foot alignment in patients with spastic pes planovalgus deformity. The purpose of the present study was to examine the long-term results of Grice-Green procedure and whether it can achieve significant correction of each of the components of pes planovalgus deformity. METHODS: Eleven children (16 feet) with cerebral palsy who underwent Grice extra-articular subtalar arthrodesis were reviewed retrospectively. The mean age of patients at the time of surgery was 9 years and 8 months (range, 6 years 5 months to 12 years 4 months). The mean followup was 3 years and 7 months (range, 2 years 1 month to 8 years 3 months). Seven radiographic parameters of each patient before surgery, after surgery and at the latest followup were used. In addition, position of the graft relative to the weightbearing axis of the tibia was evaluated. RESULTS: Most of the examined parameters showed statistically significant correction which was maintained in the long run. Moreover, the placement of the graft along the mechanical axis seemed to play an important role for stability and preservation of correction of the planovalgus deformity. On the other hand, there were three cases where the osseous graft was absorbed and two cases where triple arthrodesis was necessary due to recurrence of the deformity. CONCLUSION: Grice-Green extra-articular subtalar arthrodesis improves foot alignment in patients with spastic pes planovalgus deformity and can achieve significant correction, postoperatively as well as on a long-term basis, of each of the components of pes planovalgus deformity.

Early mobilization after uncomplicated medial subtalar dislocation provides successful functional results.

BACKGROUND: Subtalar dislocation is a rare injury, with the medial type occurring in the majority of cases. The period of postreduction immobilization is a matter of controversy. Most studies set the period of immobilization between 4 and 8 weeks. The hypothesis in this study is that a period of 2-3 weeks of immobilization in a cast, followed by early mobilization, could provide better functional results than longer periods of immobilization. MATERIALS AND METHODS: During a period of 4 years, eight patients (six men, two women) with mean age of 37.2 years and uncomplicated medial subtalar dislocation were treated in our institution. Immediate reduction under sedation and cast immobilization was provided in all cases. Our rehabilitation protocol consisted of two completed weeks of immobilization and thereafter ankle range-of-motion exercises and partial weight-bearing mobilization. Patients were followed up for a mean period of 3 years. Clinical results were evaluated using the AOFAS Ankle-Hindfoot scale. RESULTS: All patients achieved almost normal ankle range of motion and good clinical outcome (mean AOFAS score 92.25). No radiographic evidence of arthritis or avascular necrosis of the talus was detected. Two patients complained of mild pain of the hindfoot. All patients returned to daily routine activities in about 2 months from injury. CONCLUSIONS: Immediate reduction and early mobilization could be key factors for uneventful recovery of uncomplicated medial subtalar dislocation. Multicenter clinical trials are needed for further validation of our initial results. LEVEL OF EVIDENCE: III, prospective clinical series study.

Effect of combined administration of transforming growth factor-b1 and insulin-like growth factor I on the mechanical properties of a patellar tendon defect model in rabbits.

The aim of this study was to test the hypothesis that combined administration of TGF-b1 and IGF-I in a patellar tendon defect model could enhance the mechanical properties of the healed tendon. Twenty four New Zealand white rabbits were used for this purpose. In each animal, the right knee was used for the application of the growth factors, whereas the left knee served as an untreated control. The growth factors were mixed with fibrin sealant as a delivery vehicle. Two groups of rabbits were sacrificed after 2 weeks and 6 weeks respectively. Application of the growth factors resulted in a significant increase in force at failure, ultimate stress, stiffness, and energy uptake at 2 weeks, whereas none of the parameters revealed any significant difference between the two groups at 6 weeks. This study provides valuable information on the effect of the two growth factors on this patellar tendon defect model.

Temporal and spatial expression of TGF-beta1 in an Achilles tendon section model after application of platelet-rich plasma.

BACKGROUND: To investigate the effect of platelet-rich plasma (PRP) on TGF-beta1 expression during tendon healing. METHODS: We used 48 skeletally mature New Zealand White rabbits. 24 rabbits received the PRP, and 24 rabbits served as an untreated control group. Equal numbers of animals were sacrificed at 1st, 2nd, 3rd, and 4th week. The surgical procedure involved a transverse incision to transect the Achilles tendon. A volume of 1ml of PRP was then injected into the tendon mass in the PRP group. Histological and immunohistochemical evaluations with an anti-TGF-beta primary antibody were performed. RESULTS: The pattern of expression of TGF-beta1 in the PRP group was characterized by a significant upregulation during the first 2 weeks and subsequently significant downregulation in the 3rd and 4th week in comparison with the controls. CONCLUSIONS: Our results suggest that PRP may affect the tendon healing process by altering the expression of TGF-beta1.

The influence of platelet-rich plasma on angiogenesis during the early phase of tendon healing.

BACKGROUND: The poor vascularity of tendons is a major factor in their limited healing capacity. The aim of this study was to assess the effect of Platelet Rich Plasma (PRP) on angiogenesis during tendon healing. MATERIALS AND METHODS: Forty-eight skeletally mature New Zealand White rabbits were used. The Achilles tendon was transected transversely and 0.5 ml of PRP was injected into the tendon mass on each side of the incision on both limbs. The injection in the control group consisted of saline. Six animals from each group (12 tendons each) were sacrificed after 1, 2, 3, and 4 weeks following treatment. Three sections from each Achilles were stained with hematoxylinosin for microscopic examination. Further three sections were immunostained with a monoclonal antibody against CD31 (Daco Co), followed by image analysis to count new vessel numbers and statistical analysis was performed. RESULTS: There was significantly more angiogenesis in the PRP group compared to the control group during the first two weeks of the healing process, i.e., inflammatory and proliferative phase (p < 0.0001). The orientation of collagen fibers in the PRP group was better organized. The number of the newly formed vessels in the PRP group were significantly reduced at 4 weeks compared to the controls (p < 0.0001) suggesting the healing process was shortened. CONCLUSION: PRP seems to enhance neovascularization which may accelerate the healing process and promote scar tissue of better histological quality. CLINICAL RELEVANCE: Although these results need replication and further biomechanical research, PRP may promote tendon healing acceleration.

A humeral shaft fracture complicated with anterior shoulder dislocation in a young male treated with modified Intramedullary nailing prior to reduction: a case report.

INTRODUCTION: Anterior dislocation of the shoulder joint with an ipsilateral fracture of the humeral shaft is a rare injury which may require demanding technical skills. CASE PRESENTATION: A 33 years old male sustained a work accident. Radiographs showed an anterior dislocation of the shoulder with a transverse fracture of the middle third of the humeral shaft on the same side. The dislocation proved to be irreducible in the setting of the fracture humerus. Thus, stabilization of the shaft fracture was successfully applied with an intramedullary nail and a small antirotational plate prior to the reduction. The patient recovered full function of the shoulder. CONCLUSION: Performing primary intramedullary nailing of the humeral shaft fracture before manipulation of the joint resulted to an excellent outcome.

Fractures of the femoral neck treated with hemiarthroplasty. A comparative study.

INTRODUCTION: Hemiarthroplasty is the treatment of choice in the management of displaced intracapsular fractures of the proximal femur in old patients with low functional demands. AIM: To assess the effectiveness of cementless Austin-Moore and the cemented Thompson prostheses used in the treatment of displaced intracapsular fractures of the proximal femur. PATIENTS AND METHODS: We studied retrospectively 376 patients with fresh, displaced, nonpathological femur neck fractures. They were treated with either a cementless Austin-Moore prosthesis or a cemented Thompson prosthesis. Criteria for the choice of the prosthesis were the fracture site on the neck of the femur and the bone quality. The follow-up period was 3 to 8 years and the number of reviewed patients was 122. RESULTS: The Thompson prosthesis group showed slightly better results. Acetabular erosion rate was significantly lower in the uncemented group while loosening rate here was significantly higher. CONCLUSION: Advantages and disadvantages were identified in both groups although we believe that none of the approaches proved definitively superior to the other.

External fixation of intertrochanteric fractures in elderly high-risk patients.

This study concerns 56 elderly high-risk patients with an intertrochanteric fracture of the femur, who were treated with the Citieffe/Ch-N external fixator between November 2002 and February 2004. A short intraoperative time (37 minutes), no need for peroperative blood transfusion, fast mobilisation and a short hospitalisation (average 6 days, thus reducing the total cost) were noted. Union was obtained in all patients after 6 months. There was no significant difference between the functional status before the injury and at follow-up after 12 months (p > 0.05). No deep pin track or wound infections occurred, but a superficial skin reaction was seen in 39.3%. The mortality rate was 16.1% at 6 months, and 20.4% at 12 months, which contrasts favourably with other types of treatment. External fixation with this device can be used successfully for the treatment of elderly high-risk patients with intertrochanteric fractures.