Surgical Treatment of Piriformis Syndrome.

BACKGROUND: Piriformis syndrome (PS) is an uncommon disease characterized by symptoms resulting from compression/irritation of the sciatic nerve by the piriformis muscle. Uncertainty and controversy remain regarding the proper diagnosis and most effective form of treatment for PS. This study analyzes the diagnostic methods and efficacy of conservative and surgical treatments for PS. METHODS: From March 2006 to February 2013, we retrospectively reviewed 239 patients who were diagnosed with PS and screened them for eligibility according to our inclusion/exclusion criteria. All patients underwent various conservative treatments initially including activity modification, medications, physical therapy, local steroid injections into the piriformis muscle, and extracorporeal shock wave therapy for at least 3 months. We resected the piriformis muscle with/without neurolysis of the sciatic nerve in 12 patients who had intractable sciatica despite conservative treatment at least for 3 months. The average age of the patients (4 males and 8 females) was 61 years (range, 45 to 71 years). The average duration of symptoms before surgery was 22.1 months (range, 4 to 72 months), and the mean follow-up period was 22.7 months (range, 12 to 43 months). We evaluated the degree of pain and recorded the responses using a visual analog scale (VAS) preoperatively and 3 days and 12 months postoperatively. RESULTS: Buttock pain was more improved than sciatica with various conservative treatments. Compared with preoperatively, the VAS score was significantly decreased after the operation. Overall, satisfactory results were obtained in 10 patients (83%) after surgery. CONCLUSIONS: PS is thought to be an exclusively clinical diagnosis, and if the diagnosis is performed correctly, surgery can be a good treatment option in patients with refractory sciatica despite appropriate conservative treatments.

Comparison of Perioperative Blood Loss in Primary Non-cemented Total Hip Arthroplasty for Rapidly Destructive Coxarthrosis and Osteonecrosis of the Femoral Head.

PURPOSE: The purpose of this study is to compare the perioperative blood loss in primary non-cemented total hip arthroplasty (THA) performed for rapidly destructive coxarthrosis (RDC) with the perioperative blood loss in primary non-cemented THA for typical osteonecrosis of the femoral head (ONFH). MATERIALS AND METHODS: From January 2000 to December 2013, 19 patients were diagnosed with RDC (group 1) and 40 patients were diagnosed typical Ficat stage IV ONFH (group 2), comparison of perioperative blood loss between group 1 and group 2 in primary noncemented THA was done. Patients with preoperative usage of steroid or anticoagulants medication and with hemodynamic abnormal blood test results were excluded. The blood loss was measured up to the fifth post operation day and calculated with formula proposed by Mercuriali, Inghilleri and Nadler. RESULTS: Non-compensated blood loss calculated in milliliters of red blood cells was 362 mL (standard deviation [SD], 187; range, 77-675) in group 1 and 180 mL (SD, 145; range, 53-519) in group 2. Compensated blood loss was 630 mL (SD, 180; range, 380-760) in group 1 and 503 mL (SD, 260; range, 190-1, 505) in group 2. The total blood loss after primary non-cemented THA is greater when surgery is performed for RDC than for ONFH, with the volume of 992 mL (SD, 300; range, 457-1, 434) in group 1 and 683 mL (SD, 360; range, 226-1, 975) in group 2 respectively. CONCLUSION: Total perioperative blood loss was significantly greater in RDC than in ONFH in primary non-cemented THA.

Treatment of subtrochanteric nonunion of the femur: whether to leave or to exchange the previous hardware.

OBJECTIVE: Our aim was to compare the clinical results of two different methods for treatment of subtrochanteric nonunion: an additional fixation to the previous hardware, and exchange of previous hardware. METHODS: We retrospectively analyzed 19 cases of subtrochanteric nonunion, and compared clinical results from 10 cases (Group 1) with exchange of the previous hardware, and 9 cases (Group 2) with retained previous hardware and an additional fixation. Autogenous bone grafting were performed for all cases. The mean age of the patients was 49.1 years in Group 1, and 48.2 years in Group 2. The mean follow-up period was 19.3 months. RESULTS: The union rate was 100% in Group 1, and 77.8% in Group 2 (p<0.05). The average time of union was 7.6 months in Group 1, and 6.9 months in Group 2. The mean preoperative leg length discrepancy (LLD) was 8.3 mm in Group 1, 10.0 mm in Group 2; and the mean final LLD was 13.9 mm in Group 1, and 11.2 mm in Group 2. The mean length of hospital stay was 23.8±3.3 days in Group 1, and 18.2±2.7 days in Group 2; the mean amount of blood transfusion was 960 ml in Group 1, and 647 ml in Group 2; and the mean operative time was 3.7±0.8 hrs in Group 1, and 2.7±0.6 hrs in Group 2 (p<0.05). CONCLUSION: The union rate in patients with exchange of the previous hardware was better than in those with retained hardware in the treatment of subtrochanteric nonunion by complete removal of the interposed fibrous tissue and meticulous bone grafting leading to a biological environment to achieve bony union.

Influence of fragment volume on stability of 3-part intertrochanteric fracture of the femur: a biomechanical study.

Complex unstable fracture can complicate the treatment outcome of intertrochanteric fracture of the femur, and fixation failure after surgery is a significant problem in elderly patients. This study aimed to evaluate the effect of fracture geometry on the stability of 3-part intertrochanteric fracture by assessing the fragment size. Four categories (group I: large greater trochanter, small lesser trochanter; group II: large greater trochanter, large lesser trochanter; group III: small greater trochanter, small lesser trochanter; and group IV: small greater trochanter, large lesser trochanter) of a 3-part intertrochanteric fracture model were designed. Three-dimensional computer tomography scanning was performed to measure the volume of each fragment. After fixation with a dynamic hip screw, a cyclic loading study was conducted using a servohydraulic machine. There was a significant difference in fatigue failure between each group. After all specimens had endured 10,000 cycles with a range of loads (100-1,000 N), the mean number of cycles until fixation failure with a load range of 200-2,000 N was 1,467.67 ± 199.92 in group I; 579 ± 93.48, group II; 398.17 ± 37.92, group III; and 268.67 ± 19.92, group IV. Fixation strength was approximately 5 times greater in group I than in group IV. In 3-part intertrochanteric fracture, the sizes of the greater and lesser trochanteric fragments are important factors for determining stability after dynamic compression screw fixation. This study supports our hypothesis that the volumetric ratio of ∆lesser trochanter/∆greater trochanter can be used to predict stability of intertrochanteric femoral fracture.

Treatment of femoral neck fractures with bipolar hemiarthroplasty using a modified minimally invasive posterior approach in patients with neurological disorders.

Bipolar hemiarthroplasty is a useful treatment for displaced femoral neck fractures in elderly patients. Although uncommon, dislocation is problematic, particularly in older patients, and those with neurologic disorders are at an increased risk for this complication. Recently, a modified posterior approach to the hip intended to enhance hip joint stability by preserving the short external rotators was described. Therefore, the dislocation rate was compared after bipolar hemiarthroplasty using the modified or standard minimally invasive posterior approach.A retrospective analysis was performed of 67 patients older than 65 years with displaced femoral neck fractures and neurological disorders who underwent bipolar hemiarthroplasty using the modified and standard approaches in 28 and 39 hips, respectively. Follow-up averaged 19.3 months. Dislocation rates for the treatment and control groups were 0% and 7.7%, respectively (P<.01). No significant difference existed in postoperative bleeding, operative time, or length of hospital stay between groups. These data suggest a lower dislocation rate after bipolar hemiarthroplasty via the modified, short external rotator-sparing approach for treating displaced femoral neck fractures in elderly patients with neurological disorders.

Usefulness of multi-detector CT in Boyd-Griffin type 2 intertrochanteric fractures with clinical correlation.

OBJECTIVE: To investigate the usefulness of multi-detector computed tomography (MDCT) in three-part intertrochanteric fractures of proximal femur. MATERIALS AND METHODS: Twenty-six patients with Boyd-Griffin type 2 intertrochanteric fractures with MDCT (group 1) and 36 patients of the same type fracture without MDCT (group 2) were compared. Lesser trochanter (LT)/greater trochanter (GT) volume ratio above 0.5 or the volumetric proportion of GT in total volume of proximal femur below 25% was considered an unstable fracture. The fractures were fixed with dynamic compression hip screws (DCS). Additional greater trochanter stabilizing (GTS) plate or bone cement augmentation of the femoral head was performed in unstable fractures. Clinical outcome between the two groups by fixation failure and radiological results was compared. RESULTS: The volume ratio of the LT/GT was 0.33 (range, 0.13-0.73). The volume of the LT was inversely correlated with that of the GT (p < 0.001). The volume of the GT was significantly correlated with the LT/GT ratio or the head and neck (HN)/GT ratio (p < 0.001). Seven cases were regarded as unstable fractures in group 1. Fixation failures happened in one case in group 1 and five cases in group 2. There was significantly lower failure rate in group 1 than group 2 (p = 0.03). Neck-shaft angle at last follow-up was 134.8 degrees +/- 5.3 in group 1 and 131.3 degrees +/- 5.1 in group 2 (p = 0.01). The sliding length of lag screws were 5.6 degrees +/- 2.9 mm in group 1 and 8.3 degrees +/- 3.2 in group 2 (p = 0.03). CONCLUSION: Preoperative use of MDCT provides useful information about the fracture pattern and the geometry of the proximal femur in unstable intertrochanteric fractures and helps surgical planning. The ratio of the LT to the GT is inversely correlated with fracture stability.

Postoperative mortality and factors related to mortality after bipolar hemiarthroplasty in patients with femoral neck fractures.

The purpose of this study was to determine the mortality rate and factors related to mortality in elderly patients with acute and monotraumatic femoral neck fractures. This study included 241 patients with femoral neck fractures after bipolar hemiarthroplasty. We analyzed the mortality rate and the relationship between postoperative mortality and risk factors, such as age, sex, body mass index, the time to surgery, and the Society of Anesthesiologists' score. The postoperative mortality rate 1 and 3 years after surgery was 11.2% and 19.5%, respectively. There proved to be a relationship between postoperative mortality and age, the time to surgery, and the Society of Anesthesiologists score. We recommend that surgery should not be delayed, and caution should be exercised for the high-risk group patients.

A multi-center, randomized, clinical study to compare the effect and safety of autologous cultured osteoblast(Ossron) injection to treat fractures.

BACKGROUND: We performed a multicenter, open, randomized, clinical study of autologous cultured osteoblast injection for long-bone fracture, to evaluate the fracture healing acceleration effect and the safety of autologous cultured osteoblasts. METHODS: Sixty-four patients with long-bone fractures were randomly divided into two groups, i.e. those who received autologous cultured osteoblast injection and those who received no treatment. The sum of the difference in the callus formation scores after four and eight weeks, was used as the first efficacy variable. RESULTS: The autologous cultured osteoblast injection group showed fracture healing acceleration of statistical significance, and there were no specific patient complications when using this treatment. CONCLUSION: Autologous cultured osteoblast injection should therefore be considered as a successful treatment option for treating long-bone fracture.

Enhanced biocompatibility of Co-Cr implant material by Ti coating and micro-arc oxidation.

The biocompatibility of Co-Cr alloy was significantly improved by forming a rough TiO(2) layer on its surface. The TiO(2) layer was formed by coating the Co-Cr alloy with titanium (Ti) through electron beam deposition followed by microarc oxidation (MAO). When Ti was coated on the surface, the biocompatibility of the Co-Cr alloy was enhanced and it was further improved by the MAO treatment. There were close relationships between the phase, morphology, and thickness of the TiO(2) layer and the applied voltage. The biocompatibility of the specimens coated with Ti and subjected to MAO treatment was evaluated by in vitro alkaline phosphatase activity tests.

Modified posterior approach to total hip arthroplasty to enhance joint stability.

UNLABELLED: We modified the posterior approach by preserving the external rotator muscles to enhance joint stability after primary THA. We asked whether this modified posterior approach would have a lower dislocation rate than the conventional posterior approach, with and without a repair of external rotator muscles. We retrospectively divided 557 patients (670 hips) who had undergone primary THA into three groups based on how the external rotator muscles had been treated during surgery: (1) not repaired after sectioning, (2) repaired after sectioning, or (3) not sectioned and preserved. The minimum followup was 1 year. In the group with preserved external rotator muscles, we observed no dislocations; in comparison, the dislocation rates for the repaired rotator group and the no-repair group were 3.9% and 5.3%, respectively. This modified posterior approach, which preserves the short external rotator muscles, seemed effective in preventing early dislocation after primary THA. LEVEL OF EVIDENCE: Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

NF-kB signaling blockade abolishes implant particle-induced osteoclastogenesis.

In this study we investigated the effect of NF-kB signaling blockade on polymethylmethacrylate (PMMA) particle-induced osteoclastogenesis in vitro. We first established effective blockade of NF-kB activity as tested by electrophoretic mobility shift assays (EMSA). Particle-induced NF-kB activation in murine osteoclast precursor cells (CSF-1-dependent bone marrow macrophages) was markedly reduced by co-treatment of the cells with the NF-kB inhibitors N-tosyl-L-phenylalanine chloromethyl ketone (TPCK) and Calpain Inhibitor I (CPI). This inhibition of NF-kB activity was associated with blockade of p50 NF-kB subunit nuclear translocation. We then established a direct NF-kB inhibition approach by utilizing a TAT-bound, mutant IkB (TAT:IkB(46-317)), and demonstrated an inhibitory effect evidenced by decreased NF-kB DNA binding activity. Having established that these strategies (TPCK, CPI, TAT: IkB(46-317)) effectively block NF-kB activation, we next investigated the effect of these agents on particle-stimulated osteoclast formation. PMMA particle stimulation of mature osteoclast formation from RANKL-primed osteoclast precursor cells was blocked by all three inhibitors. To further test the efficacy of NF-kB blockade, experiments were performed with the TAT:IkB(46-317) mutant peptide in whole bone marrow cultures that contain supporting stromal cells. Again, this inhibitor efficiently blocked particle-induced osteoclastogenesis. Thus, we have shown that pharmaceutical and molecular blockade of NF-kB activation inhibits PMMA particle-directed osteoclastogenesis in vitro.