Satisfactory intermediate and long-term results of rotational acetabular osteotomy (RAO) for the treatment of early osteoarthritis secondary to developmental dysplasia of the hip have been reported. The purpose of this study is to examine the 30-year results of RAO.

Between 1987 and 1994, we treated 49 patients (55 hips) with RAO for diagnosis of pre- OA or early-stage OA. Of those patients, 35 patients (43 hips) were available at a minimum of 28 years. The follow-up rate was 78.2% and the mean follow-up was 30.5 years. The mean age at the time of surgery was 34 years. Clinical evaluation was performed with the Merle d'Aubigne and Postel rating scale, and radiographic analyses included measurements of the center-edge angle, acetabular roof angle, and head lateralization index on preoperative, postoperative AP radiographs of the pelvis. Postoperative joint congruency was classified into four grades. The radiographic evidence of progression of OA was defined as the minimum joint space less than 2.5mm.

The mean preoperative clinical score was 14.0, which improved to a mean of 15.3 at the time of the latest follow-up. The mean center-edge angle improved from 0.6° preoperatively to 34° postoperatively, the mean acetabular roof angle improved from 28.4°preoperatively to 1.0°postoperatively, the mean head lateralization index improved from 0.642 preoperatively to 0.59 postoperatively. Postoperative joint congruency was excellent in 11 hips, good in 29 hips, and fair in 3 hips. Nineteen patients (20 hips) had radiographic OA progression, and 10 patients (11 hips) were converted to THA. Kaplan-Meier survivorship analysis, with radiographic OA progression as the end point, predicted survival of 75.6% at 20 years and 48.8% at 30 years, and with THA conversion as the end point, 90.2% at 20 years and 71.2% at 30 years.

The RAO is an effective surgical procedure for symptomatic dysplastic hips of pre- and early-stage OA and could change the natural history of the dysplastic hip.

The transtrochanteric anterior rotational osteotomy (TRO) was developed by Sugioka as a joint-preserving procedure which prevents further deformity by transposing the necrotic area from a site of primary weight-bearing to a secondary area. We performed this procedure for children and young adults with various hip disorders.

Between 1994 and 2015 we performed TROs on 12 joints in 12 patients with SCFE (4), pigmented villonodular synovitis (2), septic arthritis (1), FAI (1), hip dysplasia (1), femoral neck fracture (2) and postoperative RAO (1). The mean age at the time of surgery was 21 years (10–43) and the mean follow-up period was 8 years (1–22). The rotational directions of the femoral head were anterior (5) and posterior (7). Clinical assessment was undertaken using the system of Merle d'Aubigné and Postel, grading pain, mobility and walking ability with scores from 0 to 6. Radiographically bone regeneration and OA progression were estimated.

The mean clinical score improved from 9.0 to 14.4 at final follow-up. Spur formation of femoral head was observed in 7 patients (58%). OA progression was in two patients (17%) and one patient was converted to THA 22 years after surgery. All cases with osteonecrosis in SCFE and femoral neck fracture showed remarkable bone regeneration.

The TRO is a reliable joint-preserving procedure for various hip disorders in children and young adults.

Introduction

Failures in fracture healing are mainly caused by a lack of neovascularization. We have previously demonstrated that G-CSF-mobilized peripheral blood (GM-PB) CD34+ cells, an endothelial progenitor enriched cell population, contributed to fracture healing via vasculogenesis and osteogenesis. We postulated the hypothesis that local transplantation of culture expanded bone marrow (cEx-BM) CD34+ cells could exhibit therapeutic potential for fracture healing.

Introduction

CXC chemokine receptor 4 (CXCR4) is a specific receptor for stromal-derived-factor 1 (SDF-1). SDF-1/CXCR4 interaction contributes to the regulation of endotherial progenitor cell (EPC) recruitment in ischemic tissues. The purpose of this study is to investigate the mechanistic function of CXCR4 on EPCs for bone fracture healing.

Introduction

The therapeutic potential of hematopoietic stem cells for fracture healing has been demonstrated with mechanistic insight of vasculogenesis and osteogenesis enhancement. Lnk has recently been proved an essential inhibitory signaling molecule in SCF-c-Kit signaling pathway for stem cell self-renewal demonstrating enhanced hematopoietic and osteogenic reconstitution in Lnk-deficient mice. We investigated the hypothesis that down regulation of Lnk enhances regenerative response via vasculogenesis and osteogenesis in fracture healing.

The purpose of this study was to elucidate the hemostatic effects of tranexamic acid (TA) in patients undergoing total knee arthroplasty (TKA) performed with different three methods.

The subjects were 89 patients (10 males, 79 females; mean age at surgery 74 years old) who underwent TKA for osteoarthritic knees in our department between April 2006 and October 2007. A cemented prosthesis (NexGen LPS flex, Zimmer) was used in all cases. The subjects were divided into three groups; Group A (n=39), in whom intravenous administration of TA (1 000 mg) 15 minutes before tourniquet release and a drain-clamping method [DC; joint filled with 50 ml of fluid that contained TA (1 000 mg, 10 ml) and 40 ml of physiological saline just after surgery] were performed, as reported by Prof. Otani (Keio Univ., Tokyo, Japan) in 2005; Group B (n=20), who had the same protocol as Group A, except that the DC Joint was filled with a total of 50 ml physiological saline alone; and group C (n=30), who received DC alone with 50 ml of physiological saline and no intravenous administration of TA. The parameters evaluated were the amounts of intra-operative bleeding, bleeding after 24 hours, total bleeding (intra- and post-operative), and changes in Hb levels between before surgery and 1 week after surgery. Statistical analyses were performed using a Mann-Whitney U-test, with P-values greater than 0.05 considered to be significant.

No differences were observed in the amount of bleeding during the TKA among the groups. In contrast, bleeding at 24 hours after surgery and total amounts of bleeding were significantly lower in Group A (281 and 695ml, respectively) as compared to Group B (337 and 868 ml, respectively) and Group C (650 and 1043 ml, respectively) (p< 0.01). In addition, Hb levels at 1 week after surgery were reduced by 1.8 g/dl in Group A, as compared to 2.3 and 3.0 g/dl in Groups B and C, respectively, demonstrating a significantly lower amount of reduction in Group A (p< 0.01).

The effect of TA for reducing blood loss in TKA is widely recognized. In the present study, concomitant use of an intravenous administration and infiltration into the joint (via DC) significantly reduced blood loss during and after TKA. Furthermore, allogenic blood transfusion could be avoided in all patients (Group A) who underwent that protocol. In our study, even when given intra-operatively, such as intravenous administration and infiltration, there were no complications. Nevertheless, when used during the post-operative course, careful attention should be paid to prevent such problems. In order to reduce blood loss during and after TKA, it is important to elucidate the optimal conditions, volume, and timing of administration of TA in future studies.

This study was conducted to investigate the cases which were obliged to receive revision surgery within the first 5 years after primary Total Knee Arthroplasty (TKA).

The subjects of this study were 15 patients (5 males & 10 females, mean age at revision 72 years) who had undertaken revision surgery within 5 years since 1996. Intervals between primary and revision TKA averaged 29.8 months. Prosthesis used for primary TKA was as follows; 11 Zimmer NexGen LPS-flex fixed bearing, 2 mobile bearing, 2 CR type.

Revised components, cause of revision, JOA score as clinical results and FTA as radiographic evaluation were examined.

Revised parts were as follows;

All components: 2,

Stemmed Femoral components were used in 6 out of 8 knees, stemmed Tibial components in 9 out of 11 knees.

The causes of revision were as follows;

infection: 1,

JOA scores improved from 45 points to 78 points, and FTA proved to be 176 deg., postoperatively.

Primary TKA remains one of the most successful orthopedic procedures. Survivorship was generally reported over 15 years in the previous article. However, there are some cases in which revision TKA is necessary by some causes. There seems to be various types of causes for revisions, such as loosening, inadequate position, abrasion of components and others. Though loosening of components due to traumatic cause was inevitable, other causes, such as inadequate position of component, imbalanced soft tissues and infection, which depend on our technique, should be cared during and after surgery. From our study, except for 7 (2 trauma, 5 unknown) out of 15 knees, almost half of revision TKA (8 knees) might be due to technical demand. As for surgical techniques, in the case of poor bony quality, we routinely use stemmed components and should try not to impact strongly on setting component to prevent from sinking. In the case of non-traumatic cause, 3 out of 12, though the position of tibial component was acceptable, tibial component sunk because of bony weakness and/or imbalanced soft tissues resulting pain.

Adequate position and balance of components should be achieved during primary TKA. In our department, we are trying to revise and routinely use stemmed components as soon as possible, when loosening of component is confirmed. Metal augmentation, if necessary, is mainly used for bone defect to do early rehabilitation.

We concluded that adequate position of components and soft tissue balance was very important at the time of primary TKA. Clinical results of revision TKA were almost equal to those of primary TKA, however, long term follow-up will be needed.

This study was conducted to investigate the correlation between intra-operative Flexion Balance (IFB) and post-operative Flexion instability in Posterior-Stabilized Total Knee Arthroplasty (TKA).

Eighty-three knees (4 males and 79 females, average 74 y/o) with primary TKA (Zimmer NexGen LPS flex fixed-bearing) for varus osteoarthritis in our hospital between January 2006 and December 2007, were included in this study. After bone-cutting independently and balancing manually, Extension Balance (EB) and IFB were measured with seesaw type tensor. Post-operative Flexion Balance (PFB) was evaluated as post-operative instability with Kanekasu’s Epicondylar view at the least more than 6 months postoperatively. Varus inclination (lateral joint opening) was indicated as plus. In addition, pre-operative standing FTA (femorotibial angle), the change of FB (CFB=PFB-IFB) and True Correction Angle (TCA=FTA-174-EB), we had defined, were calculated. The TCA was hypothesized to mean the extent of medial soft tissue release. With these data, the correlation between IFB and PFB, CFB and TCA were analyzed. Of these, furthermore, in the well-balanced knees (IFB ≥ ±2°), same analyses were done. Statistical analysis was performed with StatView software.

Each data (n=83) in all subjects was as follows (Mean ± SD, degrees.); EB: 2.74 ±2.74, IFB: 1.61 ±3.67, PFB: 1.73 ±2.66, CFB: 0.01 ±4.25, FTA: 185.3 ±6.7, TCA: 8.65 ±6.52, respectively. Though there was no correlation between IFB and PFB (r=−0.09, p=0.57), CFB was correlated with TCA (r=0.40, p< 0.01).

Each data in the well-balanced knees (n=43) was as follows, EB: 3.09 ±2.71, IFB: 0.70 ±1.30, PFB: 1.22 ±2.52, CFB: 0.57 ±2.3, FTA: 185.5 ±6.5, TCA: 8.42 ±6.09, respectively. There was a correlation between IFB and PFB (r=0.41, p< 0.01), however, FBC was not correlated with TCA (r=−0.26, p=0.10).

Same rectangular balance has been thought to be one the most important factors to obtain the good postoperative stability in TKA. For correcting alignment of lower extremity, medial or posteromedial release are generally needed to perform mainly in extended knee. Even if well-balanced EB was achieved, IFB does not necessarily prove to be well, rather than sparse. This might be because intra-operative balance was not measured under physiological condition, especially after wide posteromedial release. Soft tissues released for balancing would be repaired and shortened over time, so it seems to be natural that intra-operative balance would change. We have reported that EB was correlated with post-operative instability in the previous congress (ISTA 2006). However, it remains unknown as for FB. Our study demonstrated that CFB increased in accordance with the extent of soft tissue release (TCA), and that IFB was correlated with PFB only in the well balanced knees. This means that the measurement of IFB was not useful for predicting PFB in the imbalanced knees. That’s why we should achieve adequate balance & gap during operation and should recognize that FB was influenced by various factors, not only soft tissues but also rotation and inclination of components. In the future, how to measure IFB, including tensor and measurement condition, should be considered and established to predict knee balancing for good clinical results.