The direct anterior approach (DAA) is one of the muscle sparing approaches in total hip arthroplasty (THA). The advantages of the DAA-THA include low dislocation rate, quick recovery with less pain, and accurate implantation. However, complications related to the learning curve have been reported. The aim of this study was to analyze the first 100 cases of DAA-THA performed by 2 surgeons. The records of first 100 consecutive primary DAA-THAs performed by 2 orthopedic surgeons who have np experience of DAA-THA previously were retrospectively reviewed. All operations were performed using DAA in the supine position without the special traction table. The surgical result, the early clinical results, complications, and accuracy of prosthesis placement were investigated.Background:
Methods:
In TKA, it is important to make the equal extension and flexion gap (EG and FG) of the knee. Although, this principal concept applies to all knees, flexion contracture is known to have difficulties to achieve the equal EG and FG because of its smaller EG than usual. Whereas, it is also well known that PCL resection makes FG wider than EG, however, many surgeons recommend PCL resection in case of flection contracture because it is easy to manage during surgery, nevertheless the risk of further gap unbalance. Although, flexion contracture is not rare in TKA, the controversial problem of the PCL resection for the flexion contracture still remains even in today. To investigate this contradiction, we measured intra-operative EG and FG of the knee with 20 degree or more pre-operative flexion contracture. The gaps were measured by 3 different ways; a tension device system with 30 and 40 pound tension (group 1 and 2) and a spacer block system which had 1 mm increment thickness variation (group 3). The cases were 41, 46 and 51 knees in group 1, 2 and 3 respectively. Group 1 and 2 have overlapping in 27 knees.Introduction
Materials and methods
Although, the total knee arthroplasty (TKA) procedure is performed to make the same extension gap (EG) and flexion gap (FG) of the knee, it is not clear how the gaps can be created equally. According to earlier reports, the gaps after bone resection (bone gaps) differ from the gaps after the trial component of the femur is set (component gaps), because of the thickness of the posterior condyle of the femoral component and the tension of the posterior capsule. The surgeon can only check the component gaps after completing the bone resection and setting the trial component and it difficult to adjust the gaps even when the acquired component gaps are inadequate. To resolve this problem, we developed a “pre-cut trial component” for use in a pre-cut technique for the femoral posterior condyle (Fig. 1). This specially made trial component allows us to check the component gaps before the final bone resection of the femur. The pre-cut trial component is composed of an 8-mm-thick usual distal part and a 4-mm-thick posterior part of the femoral component, and lacks an anterior part of the femoral component. With this pre-cut trail component, 152 knees were investigated. The EG was made by standard resection of distal femur and proximal tibia. The FG was made by a 4 mm pre-cut from the posterior condylar line of the femoral posterior condyle (Fig. 2). The rotation of the pre-cut line is initially decided by anatomical landmarks. Once all of the osteophytes are removed and the bone gaps are checked, the pre-cut trial component is attached to the femur and the component gaps are estimated with the patella reduction (Fig. 3). In our experiments, these gaps were the same as the component gaps after the usual trial component was set via the measured resection technique. Finally, the femur is completely resected according to the measurements of the component gaps with the pre-cut trial component.Introduction
Materials and methods
There is no criteria to select cruciate retaining (CR) or posterior substitute (PS) component in total knee arthroplasty (TKA). In this study, extension and flexion gaps were measured intra-operatively with posterior cruciate ligament (PCL) remained to reveal characteristics of the gaps. Component type selection, CR or PS, was decided intra-operatively according to the gaps in each knee. One hundred and sixty knees with osteoarthritis were investigated. Extension gap (EG) was made by resection of 8 mm distal femur and 10 mm proximal tibia. After measurement of femoral AP size, about 4 mm bigger 4-in-1 femoral cutting guide than measured size was used for pre-cut of femoral posterior condyle[Figure 1]. With this technique, flexion gap (FG) was made 4 mm smaller than usual measured resection. The gaps were measured by a tension device with 30 pounds tension and FG was corrected by the amount of pre-cut. According to the EG and corrected FG, component type was decided. Too small FG usually needed PCL resection or (and) smaller size of femoral component to make enough final FG. On the other hand, large FG needed careful consideration to sacrifice PCL for adequate final FG. In these cases, CR component was selected usually. If necessary, soft tissue was released for good ligament balance. As the final step of the surgical procedure, the size of femoral component was decided for adequate final FG. It was changeable up to 4 mm larger than measured size[Figure 2].Introduction
Materials and methods
Patients with Bertolotti’s syndrome have characteristic lumbosacral anomalies and often have severe sciatica. We describe a patient with this syndrome in whom standard decompression of the affected nerve root failed, but endoscopic lumbosacral extraforaminal decompression relieved the symptoms. We suggest that the intractable sciatica in this syndrome could arise from impingement of the nerve root extraforaminally by compression caused by the enlarged transverse process.
We usually plan surgery for total hip arthroplasty (THA)using pre-operative X-ray templates. However, the technique provides only two dimensional (2D) images and therefore has limitations for planning three-dimensional (3D) objects. Recently it has become possible to describe 3D images using computer programs that use free down loaded computer software (Hip-op) that enable comparison between 3D templates obtained by computed tomography (CT) and 2D conventional X-ray templates. Six hip joints in 6 patients (1 male, 5 females; age range at the time of operation, 49–77 years) were evaluated. Five of the patients suffered from secondary osteoarthritis of the hip (secondary OA), while the remaining patient suffered from osteonecrosis of the femoral head (ONFH). All the patients underwent THA using a cement less femoral stem (ANCA-FIT Wright Medical Technology, Arlington, Tennessee, USA). Pre-operative planning was performed using Hip-op software (Rizzoli Institute, Bologna, Italy). After the THA surgery, we carried out a repeat CT scan that was used to analyze stem fitting in the femur. In all the patients it proved easy to obtain the pre-operative template. In 4 patients, the correct stem size was selected pre-operatively, while in the other 2 patients, the planned stem size was one size smaller than that actually implanted. In the 4 patients in whom the correct stem was selected, 2 had their template correctly assessed by conventional 2D images, 1 patient’s template was one size smaller than the implant, while the remaining patient’s template was two sizes smaller than the implant. In the 2 patients who received implants one size smaller than the CT template, 1 patient had the stem inserted in the virus position while in the other patient a fracture occurred during implantation Preoperative planning for THA using a CT-based computer templating system proved to be a useful technique for the orthopedic surgeons.
