Biplane opening wedge high tibial osteotomy with a distal tuberosity osteotomy, radiological and clinical analysis with minimum follow-up of 2 Years

Background: High tibial osteotomy is an established and helpful treatment for unicompatimental osteoarthritis associated with varus deformity. However, asupratubercle high tibial osteotomy leads to a decrease in patellar height making the technique not suitable in case of concomitant patella baja. Moreover, this kind of osteotomy can change in situ forces at patellofemoral joint and the lateral patellar tilt. With the aim to widen the indication of high tibial osteotomy was proposed a biplane opening wedge high tibial osteotomy with a distal tuberosity osteotomy (B-OWHTO). This technique provide that the tibial tuberosity remains joined to the tibial metaphysis so as not to theoretically alter the patellar height. However, some Authors claim that BOWHTO could lead to an increase in tibial slope. The purpose of the present study was to assess the tibial slope, patella-femoral changes and axial correction as well as functional outcomes following a B-OWHTO. Methods: Patients operated on with a B-OWHTO and a minimum 24 months of follow-up were included. The mechanical alignment of the lower limb, patellar height, lateral patellar tilt and posterior tibial slope were calculated preoperatively, immediately after surgery and at the 24-month follow-up. The clinical results were evaluated using the Lysholm, Kujala and Hospital for Special Surgery knee scores. The possible postoperative development of patellofemoral pain or radiologic patellofemoral alteration was also evaluated. Results: Twenty-three patients were included with a mean follow-up of 33 months (range 27-41). The mechanical alignment of the lower limb shifted from a mean 9.3º ± 2.5 varus preoperatively to a mean 0.2º ± 2.2 valgus postoperatively. No changes in patellar height, lateral patellar tilt or in the posterior tibial slope were observed. The mean Lysholm and HSS scores improved from 68.3 ± 9.1 and 64.2 ± 5.2 preoperatively to 93.2 ± 2.1 and 94.1 ± 3.6 at final follow-up (p < 0.01). The mean Kujala score improved from 67.3 ± 9.8 to 86.4 ± 7.6 at final follow up (p < 0.01). No patients developed both radiological or clinical symptoms at patellofemoral joint. Conclusions: Open wedge high tibial osteotomy with a dihedral L-cut distal and posterior to the tibial tubercle accurately corrected axial malalignment without any change at patella-femoral joint or any modification to the posterior tibial slope while providing improved knee function at short-term follow-up. The radiographic as well as the clinical results support the use of this technique to treat medial compartment knee osteoarthritis and varus malalignment in young and middle-aged patients with a normal-to-low patellar height

The influence of open and closed high tibial osteotomy on dynamic patellar tracking: a biomechanical study.

Contains fulltext : 52404.pdf (publisher's version ) (Open Access)High tibial osteotomy (HTO) can cause alterations in patellar height, depending on the surgical technique, the amount of correction and the postoperative management. Alterations in patella location after HTO may lead to postoperative complications. However, information on changes in dynamic patellar kinematics following HTO is very limited. We conducted a biomechanical study, to analyze the effect of open (OWO) and closed wedge osteotomy (CWO) on patellar tracking. Using an inventive experimental set-up, we studied the 3D dynamic patellar tracking in ten cadaver knees before and after valgus HTO. In each specimen, corrections of 7 degrees and 15 degrees of valgus according to, both, the OWO and CWO technique, were performed. Patellar height significantly increased with CWO and decreased with OWO. Both, OWO and CWO led to significant changes in the patellar tracking parameters tilt and rotation. We also found significant differences between OWO and CWO. Valgus high tibial osteotomy increased the medial patellar tilt and reduced the medial patellar rotation. These effects were more profound after OWO. No significant differences were found for the effect on medial-lateral patellar translation. These observations can be taken into consideration in the decision whether to perform an OWO or a CWO in a patient with medial compartment osteoarthritis of the knee

The UniSpacer™: correcting varus malalignment in medial gonarthrosis

While options for operative treatment of leg axis varus malalignment in patients with medial gonarthrosis include several established procedures, such as unicompartmental knee arthroplasty (UKA), total knee arthroplasty (TKA) or high tibial osteotomy (HTO), there has been little focus on a less invasive option introduced more recently: the UniSpacer™ implant, a self-centering, metallic interpositional device for the knee. This study evaluates clinical and radiological results of the UniSpacer™, whether alignment correction can be achieved by UniSpacer™ arthroplasty and alignment change in the first five postoperative years. Anteroposterior long leg stance radiographs of 20 legs were digitally analysed to assess alignment change: two relevant angles and the deviation of the mechanical axis of the leg were analysed before and after surgery. Additionally, the change of the postoperative alignment was determined one and five years postoperatively. Analysing the mechanical tibiofemoral angle, a significant leg axis correction was achieved, with a mean valgus change of 4.7 ± 1.9°; a varus change occurred in the first postoperative year, while there was no significant further change of alignment seen five years after surgery. The UniSpacer™ corrects malalignment in patients with medial gonarthrosis; however, a likely postoperative change in alignment due to implant adaptation to the joint must be considered before implantation. Our results show that good clinical and functional results can be achieved after UniSpacer™ arthroplasty. However, four of 19 knees had to be revised to a TKA or UKA due to persistent pain, which is an unacceptably high revision rate when looking at the alternative treatment options of medial osteoarthritis of the knee

Harvesting local cylinder autograft from adjacent vertebral body for anterior lumbar interbody fusion: surgical technique, operative feasibility and preliminary clinical results

Autogenous iliac crest has long served as the gold standard for anterior lumbar arthrodesis although added morbidity results from the bone graft harvest. Therefore, femoral ring allograft, or cages, have been used to decrease the morbidity of iliac crest bone harvesting. More recently, an experimental study in the animal showed that harvesting local bone from the anterior vertebral body and replacing the void by a radio-opaque β-tricalcium phosphate plug was a valid concept. However, such a concept precludes theoretically the use of posterior pedicle screw fixation. At one institution a consecutive series of 21 patients underwent single- or multiple-level circumferential lumbar fusion with anterior cages and posterior pedicle screws. All cages were filled with cancellous bone harvested from the adjacent vertebral body, and the vertebral body defect was filled with a β-tricalcium phosphate plug. The indications for surgery were failed conservative treatment of a lumbar degenerative disc disease or spondylolisthesis. The purpose of this study, therefore, was to report on the surgical technique, operative feasibility, safety, benefits, and drawbacks of this technique with our primary clinical experience. An independent researcher reviewed all data that had been collected prospectively from the onset of the study. The average age of the patients was 39.9 (26–57) years. Bone grafts were successfully harvested from 28 vertebral bodies in all but one patient whose anterior procedure was aborted due to difficulty in freeing the left common iliac vein. This case was converted to a transforaminal interbody fusion (TLIF). There was no major vascular injury. Blood loss of the anterior procedure averaged 250 ml (50–350 ml). One tricalcium phosphate bone plug was broken during its insertion, and one endplate was broken because of wrong surgical technique, which did not affect the final outcome. One patient had a right lumbar plexopathy that was not related to this special technique. There was no retrograde ejaculation, infection or pseudoarthrosis. One patient experienced a deep venous thrombosis. At the last follow up (mean 28 months) all patients had a solid lumbar spine fusion. At the 6-month follow up, the pain as assessed on the visual analog scale (VAS) decreased from 6.9 to 4.5 (33% decrease), and the Oswestry disability index (ODI) reduced from 48.0 to 31.7 with a 34% reduction. However, at 2 years follow up there was a trend for increase in the ODI (35) and VAS (5). The data in this study suggest that harvesting a cylinder of autograft from the adjacent vertebral body is safe and efficient. Filling of the void defect with a β-tricalcium phosphate plug does not preclude the use of posterior pedicle screw stabilization