We have studied the correlation between the prevention of progressive collapse and the ratio of the intact articular surface of the femoral head, after transtrochanteric rotational osteotomy for osteonecrosis. We used probit analysis on 125 hips in order to assess the ratio necessary to prevent progressive radiological collapse over a ten-year period. The results show that a minimum postoperative intact ratio of 34% was required. This critical ratio may be useful for surgical planning and in assessing the natural history of the condition

Segmental collapse occurs in the early stage of a vascular necrosis (AVN) of the femoral head, and is associated with a poor prognosis. Since it develops at a relatively young age, the long-term outcome after total hip replacement is a major concern. We have compared the long-term results of pedicle bone grafting (PBG) with those of transtrochanteric rotational osteotomy (TRO). In the PBG group there were 23 men (27 hips) and three women (4 hips) with a mean age at the time of surgery of 38 years and a mean follow-up of 13 years. In the TRO group there were 44 men (55 hips) and 19 women (22 hips) with a mean age at the time of surgery of 39 years and a mean follow-up of seven years. Failure was defined as a need for total hip replacement or a Harris hip score below 70. The long-term results were similar for the two groups. The survival rates at five and ten years were 85% and 67%, respectively, in the PBG group, and 71% and 61%, respectively, in the TRO group, according to Kaplan-Meier survivorship analysis. In the TRO group patients in stage II had significantly better results that those in stage III

We reviewed 18 hips in 17 patients at a mean of five years after performing Sugioka's transtrochanteric anterior rotational osteotomy for avascular necrosis. The results were satisfactory in only three hips (17%). Twelve hips had been revised by hip replacement, revision was pending in one and two others were unsatisfactory. Hip replacement was not compromised by the previous Sugioka osteotomy. Fifteen hips (83%) had shown further collapse of the femoral head, and we conclude from this and from isotope scans that the osteotomy may have impaired the residual blood supply of the femoral head. It seems that ethnic origin may be a factor in the outcome of this procedure; we have abandoned its use

We studied nine patients who had had a transtrochanteric anterior rotational osteotomy, as developed by Sugioka, for osteonecrosis of the femoral head. At a mean of 2.5 years after the initial operation we carried out a histological study of the previously necrotic femoral head which had not shown collapse of the new primary weight-bearing site. In seven joints, there was proliferation of fibrous tissue in the dead trabeculae with vascular ingrowth. New bone covering dead trabeculae created the characteristic appearance of ‘creeping substitution’. However, these changes were limited and did not extend over the entire necrotic area. Dead bone remained in all the cases. In the other two heads we did not observe proliferation of fibrous tissue or vascular ingrowth, only dead trabeculae and dead bone marrow

Aims. Transtrochanteric rotational osteotomy (TRO) is performed for young patients with non-traumatic osteonecrosis of the femoral head (ONFH) to preserve the hip. We aimed to investigate the long-term outcomes and the risk factors for failure 15 years after this procedure. Patients and Methods. This study included 95 patients (111 hips) with a mean age of 40 years (21 to 64) who underwent TRO for ONFH. The mean follow-up was 18.2 years (3 to 26). Kaplan–Meier survivorship analyses were performed with conversion to total hip arthroplasty (THA) and radiological failure due to secondary collapse of the femoral head or osteoarthritic changes as the endpoint. Multivariate analyses were performed to assess risk factors for each outcome. Results. Survival rates at 15 years with conversion to THA and radiological failure as the endpoint were 59% (95% confidence interval (CI) 49 to 67) and 30% (95% CI 22 to 39), respectively. Necrotic type C2 ONFH (lesions extending laterally to the acetabular edge) (hazards ratio (HR) 3.9) and age > 40 years (HR 2.5) were risk factors for conversion to THA. Stage > 3a ONFH (HR 2.0) and age > 40 years (HR 1.9) were risk factors for radiological failure. Conclusion. The 15 year outcomes after TRO for ONFH are unfavorable because osteoarthritic changes occur after five years post-operatively. Cite this article: Bone Joint J 2017;99-B:175–83

We treated patients with severe slipped capital femoral epiphysisor SCFE with a posterior tilt angle or PTA of greater than or equal to 60 degrees with a Sugioka transtrochanteric rotational osteotomy. We report on the clinical and radiologic results of tis method. The study was performed on 8 cases (including 9 hips) of slipped capital femoral epiphysis, for which transtrochanteric rotational osteotomy of femoral head (Sugioka method) was carried out in author’s department from 1987 to 1996. The age of onset ranged from 9 to 14 years old (average: 11.6 years). There were 4 boys (4 hips) and 4 girls (5 hips). The follow-up period ranged from 2 years to 10 years (average: 4.4 years). Three of the treated hips were classified as chronic and 6 as acute on chronic. Preoperative head-neck angle (HNA) was 64 – 83 degrees (average: 68 degrees). All patients were performed a transtrochanteric rotational osteotomy of the femoral head which is known as the Sugioka method. The rotational angle was from 70 degrees to 90 degrees. The presence of pain, postoperative range of motion, PTA on postoperative X-rays, avascular necrosis and osteoarthritic change were examined as part of the evaluation of the clinical results. Necrosis of femoral head was found in one case, while no pain was noted in the other cases, and the range of motion was generally satisfactory. In the radiologic results, PTA was improved to 10 – 25 degrees (average: 18.5 degrees). Necrosis of femoral head was observed in one hip, but the results were satisfactory in 7 cases (8 hips). These results suggest that this technique is useful for the treatment of severe cases of slipped capital femoral epiphysis

Introduction. The purpose of this study was to investigate the long-term outcome of Sugioka's transtrochanteric rotational osteotomy (TRO) for nontraumatic osteonecrosis of the femoral head. Methods. Seventy-eight patients (87 hips) were consecutively treated by TRO from 1989 to 1994. All patients followed 15 years or more were included. Four patients (4 hips) with traumatic osteonecrosis and five patients (5 hips) followed less than 15 years were excluded. A total of 69 patients (78 hips) were included. Average age at the time of operation was 42 years. There were 51 men (57 hips) and 18 women (21 hips). The average follow-up was 17 years (range, 15 to 20 years). Type of osteonecrosis was as follows: Type B; 2 hips, Type C1; 50 hips, and Type C2; 26 hips. Stage was as follows: stage 2; 29 hips, stage 3A; 34 hips, stage 3B; 13 hips, and stage 4; 2 hips. Transtrochanteric anterior rotational osteotomy was performed in 76 hips and posterior rotational osteotomy was performed in 2 hips. Clinical evaluation was evaluated by Harris hip score. Kaplan-Meier survivorship analysis was performed based on the end point of conversion to total hip arthroplasty (THA) or re-collapse. Results. Twenty-nine hips (37.2%) were converted to THA, and 38 hips (48.7%) were re-collapsed. Average Harris hip score before operation was improved from 67 to 82 points at final follow-up. The reasons for conversion to THA within five years after osteotomy were cervical fracture or fixation failure, and 10 years after osteotomy progression of osteoarthritis due to re-collapse. Kaplan-Meier survivorship at 10 years after surgery was 69.2% (95% confidence interval: 58.8-79.6) and 15 years after surgery was 61.3% (95% CI: 49.9-72.7) with THA as the end-point. Kaplan-Meier survivorship at 10 years after surgery 50.0% (95% CI: 38.6-61.4) and at 15 years after surgery 50.0% (95% CI: 38.6-61.4) when re-collapse was defined as the end point. Type C1 was significantly better than Type C2. There was no significant difference between the corticosteroid-induced and non-corticosteroid-induced patients. There was no significant difference between the patients with early and late stage. Conclusion. The long-term outcome of transtrochanteric rotational osteotomy for osteonecrosis of the femoral head was excellent. Sixty-three percent of the hips were not converted to THA. Type C2 was a significant risk factor for TRO

The rate of success of transtrochanteric rotational osteotomy for osteonecrosis of the femoral head may be improved if patients are preselected using MRI. We have used three criteria for selection for osteotomy (i) minor collapse of the infarcted area, loss of congruity or the crescent sign, without narrowing of the joint space or acetabular involvement (ii) patients younger than 55 years and with a painful hip (iii) patients with an intact area constituting an arc of more than 120° between the central vertical line of the femoral head and the posterior or anterior margin of the necrotic portion as seen on a midsagittal MRI. Seventeen patients were selected, with a follow-up of more than 42 months. A bone scan four weeks after operation showed adequate perfusion of the proximal segment in all hips. The hip score of Merle d’Aubigné et al improved from 13.5 points before operation to 17.2 points at the latest follow-up. Further collapse of the femoral head did not occur. The use of MRI instead of plain radiographs for the selection of patients has improved the success rate of transtrochanteric rotational osteotomy

Introduction: The transtrochanteric rotational osteotomy according to Sugioka is used to preserve the femoral head and to prevent secondary osteoarthritis in young patients with osteonecrosis of the femoral head. Several Japanese studies showed favorable results, but European and American studies were disappointing. However, many factors could be responsible for this outcome including race dependent differences and the followed post-operative rehabilitation program. The purpose of our study was to investigate this transtrochanteric rotational osteotomy in Caucasian patients with osteonecrosis in which we followed the original method of Sugioka as close as possible including a 6 months period of non-weightbearing. Methods: In a single surgeon prospective study we included 26 hips in 22 consecutive patients who were followed for 8.7 years (range, 6.6–10 years) after surgery. The average age at time of surgery was thirty-two years (range, 22–49 years). No patient was lost to follow up. According the ARCO classification, 7 hips were in stage 2, 2 hips in stage 3 early and 17 hips in stage 3 late. Results: At review 17 hips had been converted to total hip arthroplasty; 2 for infection, 3 for failed osteosyntheses or non-healing of the osteotomy, 12 for progressive osteoarthritis. Taking conversion to total hip arthroplasty for any reason or Harris Hip Score below 70 as endpoint, the clinical survival rate using the Kaplan-Meier analysis was 56 per cent after 7 years (95% C.I. 36–76%). Patients with a higher age at time of surgery had a tendency to a lower clinical survival rate. Taking conversion to total hip arthroplasty, progression of collapse of the femoral head or progression of osteoarthritis of the femoral head as endpoint, the radiological survival rate using the Kaplan-Meier analysis was 89 per cent after 1 year (95% C.I. 68–100%) for patients without pre-operative collapse of the femoral head. For patients with a pre-operative collapse of the femoral head, this survival rate was 35 per cent after 1 year (95% C.I. 13–58%). Conclusion: Even after excluding the failures due to problems with osteosynthesis the results were not satisfying and the osteoarthritic process was not delayed in an effective way. Based on our results we cannot recommend this technique as an alternative for total hip arthroplasty in Caucasians

Introduction. Advanced stage and a large area of necrotic bone are known risk factors for failure after transtrochanteric rotational osteotomy of the hip in patients with osteonecrosis. The purpose of this study was to determine whether there were other risk factors for failure of this osteotomy. Methods. One hundred and five patients (113 hips) underwent transtrochanteric anterior rotational osteotomy for femoral head osteonecrosis and were followed for a mean period of 51 months post-operatively. Radiographic failure was defined as secondary collapse or osteoarthritic change. Multivariate analysis with the use of a Cox proportional-hazards frailty model was performed to assess factors that influenced the secondary collapse and osteophyte formation. A Kaplan-Meier product-limit method was performed to estimate survival. Results. Secondary collapse occurred in twenty-seven hips (23.9%) and fourteen of these hips (12.4%) were converted to a total hip arthroplasty. At the most recent follow-up, Merle d'Aubigne and Postel hip scores ranged from 6 to 18 points (mean, 16 points). Multivariate analysis showed that the stage of necrosis (hazard ratio=3.28; 95% confidence interval=1.49-7.24), age of the patient (hazard ratio=1.08; 95% confidence interval=1.02-1.14), body mass index (hazard ratio=1.19; 95% confidence interval=1.03-1.38), and extent of necrosis (hazard ratio=1.08; 95% confidence interval=1.04-1.11) were associated with secondary collapse. Seven of eighty-six hips without collapse progressed to osteoarthritis. Survivorship with total hip arthroplasty and radiographic failure as endpoints was 63.4% (95% confidence interval=51.1%-75.7%) and survivorship with total hip arthroplasty, radiographic failure, and loss of follow-up as endpoints was 56.0% (95% confidence interval=44.6%-67.4%) at 110 months. Conclusion. Our study showed that age, body mass index, stage, and extent of osteonecrosis were determining factors for secondary collapse, subsequent unsatisfactory clinical results, and conversion to total hip arthroplasty. These factors should be considered in patient selection for the osteotomy

Introduction: The aim of this study was to report the clinical and radiographic results of a modified transtrochanteric rotational osteotomy (MTRO) for osteonecrosis of the femoral head. Materials and Methods: A MTRO was performed in 43 hips with osteonecrosis. The mean age was 34 years (range, 20 to 51 years). According to the classification system of the Association Research Circulation Osseous, 17 hips were stage 2 and 26 stage 3. We performed simple MTRO in 15 cases, combination of MTRO and simple bone grafting in 3 cases, and a combination of MTRO and muscle pedicle bone grafting in 25 cases. Results: At a mean 37 months after surgery, there was further collapse of the femoral head in 3 hips. All these lesions were in the lateral location, and 2 were large lesions. One of these 3 hips was converted to a total hip arthroplasty. The overall survival rate was 93 percent. Among the surviving 40 cases, excellent results were obtained in 26 hips, good results in 11, and fair results in 3 hips. Conclusion: A MTRO is an effective method for delaying the progression of collapse in the treatment of osteonecrosis of the femoral head in selected cases

Transtrochanteric rotational osteotomy (TRO) is a controversial procedure with reported inconsistent results. We reviewed 50 patients (60 hips) who underwent this procedure for extensive osteonecrosis of the femoral head, focusing on varization to determine its effectiveness as a head-preserving procedure in young adults. The mean age of the patients was 28 years (range, 18–46 years). Using the Ficat-Arlet classification, 40 hips had Stage II and 20 hips had Stage III involvement. According to the classification system of Shimizu et al., the extent of the lesions were Grade C in 54 hips and Grade B in six hips; the location of the lesions were Grade c in 56 hips and Grade b in four hips. Minimum follow-up was 18 months (mean, 84 months; range, 18–156 months). The mean preoperative Harris hip score was 44.7 points (range, 32–62 points) which improved to an average postoperative score of 80.1 points (range, 44–100 points) at the latest follow-up. Forty-four hips showed no radiographic evidence of progression of collapse. Ten hips showed progressive collapse, seven hips showed progressive varus deformity, three hips had stress fractures of the femoral neck, and one hip had infection. We believe TRO with varization is worth attempting for extensive osteonecrosis of the femoral head in young adults, although failures and complications are not uncommon

We reviewed 41 hips in 40 patients at three to 11 years (average 6.3 years) after Sugioka transtrochanteric rotational osteotomy for non-traumatic avascular necrosis of the femoral head. The clinical results were excellent or good in 23 hips (56%) and the radiological success rate was 56%. Failure was due to fracture of the femoral neck, nonunion of the osteotomy, secondary collapse, or osteoarthritis. Nonunion and femoral neck fracture were more common after the use of the large screws described by Sugioka than with AO blade plates. Secondary collapse was significantly more common when less than one-third of the posterior articular surface was intact (p = 0.002). Postoperative degenerative changes were seen in cases with stage III avascular necrosis. We conclude that success depends to a large extent on the amount and stage of necrosis of the femoral head, but that careful technique and the use of AO hip plates may increase the likelihood of a satisfactory result

Introduction: The results of transtrochanteric rotational osteotomies for osteonecrosis of the femoral head were reviewed. Materials and Methods: The results of 26 transtrochanteric osteotomy in 24 patients with Ficat stage II or stage III osteonecrosis of the femoral head performed between April 1994 and June 2001 were evaluated. Osteotomy was primarily conducted on patients younger than 50 years of age when the necrotic lesion was at least 30% of the whole femoral head and was located at the superior aspect. Twenty-three hips in 22 patients were available for clinical and radiological follow-up at 59 months (range, 24–109 months). The average age of the patients at the time of the index procedure was 35 years (range, 23–51 years). The results were considered successful if there was no radiologic failure (progression to necrosis, further collapse) or clinical failure (the need for total hip arthroplasty). Results: Eighteen (78%) hips had a successful result. Two hips showed progressive varus deformity and were treated by valgus osteotomy. One hip survived and one hip underwent a Girdlestone operation followed by total hip arthroplasty to treat an associated deep infection. Four other hips were also subsequently treated with total hip arthropalsty because of head collapse with severe varus deformity or neck fracture in three hips and infection after osteotomy in one hip. Discussion: Our results suggest that transtrochanteric osteotomy is a dependable procedure in the treatment of a large lesion even in the later stages of osteonecrosis of the femoral head, which is especially true for patients under the age of 50 years

Introduction: Results of primary total hip arthoplasty (THA) for osteonecrosis of the femoral head are improving with newer cementation techniques and components. However not much is known about results of THA after an initial femoral head preserving procedure. The purpose of this study is to compare the complications and the clinical and radiological outcome of THA after failed transtrochanteric rotational osteotomy (Sugioka technique) (THA after TRO) and THA after failed bone impaction grafting (THA after BIG) for osteonecrosis of the femoral head. Methods: In this retrospective comparative study, sixteen cemented THA after TRO and seventeen cemented THA after BIG were performed from 1994 to 2004. These groups were compared at a minimum follow-up time of two years. The average age at time of THA was 35 years in the THA after TRO group and 39 in the THA after BIG group. Results: In THA after TRO, perioperative blood loss was significantly increased, operation time was significantly longer, and hospital admission was significantly longer compared with THA after BIG. In THA after TRO, 4 patients required re-operations because of infection (2) and dislocations (2) compared to one re-operation in THA after BIG (revision of acetabular cup). A radiolucency of the cup without re-operation was observed in one patient in the THA after TRO group. The average Harris Hip Score (HHS) in THA after TRO improved from 52 points prior to THA to 89 points at time of review and in the THA after BIG group from 42 to 91 points with a higher rise of HHS per year of follow-up. Discussion: We conclude that a THA after TRO was technically more demanding with a higher rate of complications and re-operations compared to THA after BIG. However, because of the small groups, no significant difference in outcome was demonstrated

Aims: In younger patients with dysplastic hip we come to the polemic Ð THR or joint-saving operation? The purpose of this presentation is to introduce the indications and the results of joint-saving operations as performed at our department. Methods: We analyzed patients with dysplastic hip, who undergone a joint-saving surgery at our department in past years 1997 Ð 2002. As those were younger patients, we indicated osteotomy Ð Chiari, Salter, Dega as well as pelvic osteotomy with the use of bone allograft. In all the patients we also performed a debridement and intertrochanteric osteotomy. In patients with signs of femoral head necrosis we performed transtrochanteric rotation osteotomy sec Sugioka. The postoperative following of the patients was 6 months to 5 years. Results: In years 1997 Ð 2002 we performed 7500 operations, 62 of them were pelvic osteotomies combined with intertrochanteric osteotomy and debridement of the hip. The age of patients varied between 18 and 68 years, 37 of them were women and 25 men. Oldest men was 58, youngest 24 years, oldest woman was 68 years and the youngest one was 18 years old. In 22 patients (35,5%) the results were very good, in 29 patients (46,8%) patients the results were good, in 3 patients (4,8%) the results were not sufþcient. In 8 patients (12,9%) the state remained unchanged. Conclusions: The results of above mentioned operations performed at The 2nd Department of Orthopaedic at the Faculty of Medicine of Comenius University, Bratislava, show good results. We continue indicating the combined one-stage osteotomy of the pelvis with intertrochanteric osteotomy and debridement of the hip

Introduction. Even in localized collapse due to osteonecrosis of the femoral head, a femoral head can be preserved by rotational osteotomy. In addition to anterior rotation, originally described by Sugioka, much more correction can be obtained by posterior rotation. But, transtrochanteric rotational osteotomy needs rather extensive soft tissue release, such as complete capsulotomy and resection of short external rotators and psoas tendons. Many patients tend to complain about the leg length discrepancy and limp due to varus change. We found soft tissue resection and limb shortening could be minimized by doing the osteotomy at the femur neck rather than the trochanteric area following the technique of surgical dislocation. It needs careful dissection of the posterior retinacular artery to preserve circulation to the femoral head. Methods. We have performed 17 cases (14 cases were in men and 3 cases were in women), and average patient age was 45 years old. Osteotomy was applied to cases with collapse or large necrotic region that seemed to be fail by core decompression. All cases showed collapse except one (ARCO 2-B) and 6 cases were ARCO 3-A, 5 cases were ARCO 3-B, 4 cases were ARCO 3-C and one case was ARCO stage 4. Seven cases were rotated anteriorly, and ten cases were rotated posteriorly. Amount of rotation was 63 to 170 degrees in posterior rotation (mean 100.8 degrees) and mean 48 degrees in anterior rotation. The size of the necrotic area was 301 degrees according to the Koo method (combined necrotic angle in mid-coronal and mid-saggital MRI scan). Results. Harris hip scores were improved from 62 to 88 points and VAS was from 8.4 to 2.6 in 13 cases. Conversion to THA was done in 4 cases (23.5%) as pain was persisting and there was one more failed case which was lost to follow-up. Another 2 cases showed insufficient circulation in bone SPECT, but no symptoms until recently. Problems with fixatives were in 4 cases and one case had heterotopic ossification without symptom. Conclusion. In conclusion, the outcome of the operation could be identified much earlier than other procedures. 12 cases (58.8%) showed satisfactory results and 2 cases were in observation due to insufficient circulation, and 5 cases (29.4%) failed. The operative technique will be revised and we are expecting better results

Introduction: The purpose of this study was to evaluate the clinical results of Sugioka’s transtrochanteric rotational osteotomy (TRO) for osteonecrosis of the femoral head. Materials and Methods: We reviewed 54 hips in 49 patients who underwent TRO between 1986 and 1998 (follow-up rate was 90%). The mean age of patients was thirty-six years. The average duration of follow-up was 116 months (range, 60 to 201 months). Risk factors for osteonecrosis was steroids in 23 patients, idiopathic in 15 patients, alcohol in 13 patients, and others in three patients. Using the staging system of The Japanese Investigation Committee of the Ministry of Health and Welfare, 16 hips were in Stage 2, 23 hips in Stage 3A, 13 hips in Stage 3B, and two hips in Stage 4. Clinical assessments were made according to the Japanese Orthopaedics Association hip scoring system (JOA score). Results: The overall results were excellent (JOA score of 90 to 100 points) in 22 hips (40.7%), good (80 to 89 points) in 16 hips (29.6%), fair (65 to 79 points) in 3 hips (5.5%), and poor (fewer than 64 points) in 13 hips (24.1%). The result was influenced by post-operative complications, the ratio of transposed intact femoral articular surface to the acetabular weight-bearing area after TRO, and the pre-operative stage. All hips with a ratio less than 40% showed progressive collapse. All Stage 2 hips with the ratio more than 40% showed excellent or good results. Conversely, 19% and 25% of the hips were fair or poor in Stage 3A and 3B hips even though the ratio was more than 40%. All Stage 4 hips had poor results. Discussion: We conclude that satisfactory results can be achieved using TRO by maintaining exact surgical technique and by limiting the surgical indications. The hips in early or intermediate stages with sufficient intact area are good candidates for TRO

Introduction. The purpose of this study was to examine if Sugioka's transtrochanteric rotational osteotomy (TRO) of the femoral head could be a valid option in treating idiopathic osteonecrosis of the femoral head. Methods. Thirty-two TROs performed in 29 patients between 1985 and 2006 were studied. Patient age at operation ranged from 16 to 56 years (average, 36 years). Thirteen hips were in women and 19 hips in men. Height was 165 cm and weight 63 kg (Body Mass Index 23) on average. Risk factors were corticosteroid use in 18 hips and excessive alcohol consumption in 15 hips (2 of them had both backgrounds), while neither of them was found with 1 hip. Bilateral hips were affected in 19 patients and 3 of them underwent bilateral TROs sequentially. The femoral head was rotated anteriorly in 26 hips and posteriorly in 6 hips. For fixation of the osteotomy site, large femoral screws had been used till 1995 (Group 1, 9 hips), and since 1996 an AO angle plate or a compression hip screw has been used (Group 2, 13 hips). Since 2003, pre-operative planning was performed more meticulously and the distal part of the joint capsule was cut after osteotomy as described by Atsumi (Group 3, 10 hips). The average follow-up period was 6.5 years (range, 2 to 21 years). Results. The average Japanese Orthopaedic Association hip score was 55 points pre-operatively, 63 points at 1 year, and 61 points at the latest follow-up. With pain increase, re-collapse of the rotated femoral head, fracture of the proximal fragment, nonunion, trochanteric detachment, joint space narrowing, osteoarthritic changes, or infection as the endpoint, the survival rate was 58% at 1 year, 53% at 4 - 9 years. The endpoint developed in 14 hips (re-collapse of the rotated femoral head in 9, fracture of the proximal fragment in 3, joint space narrowing in 1, and infection in 1). The changes in the surgical techniques were suggested to have improved the 3-year survivorship: 25% in Group 1, 54% in Group 2, and 74% in Group 3. The 4- to 9-year survival of this procedure was 53%. The majority of the endpoints developed within the first year, which may suggest that most of them were surgery-related. Conclusion. This procedure requires precise and meticulous precautions in pre-operative planning, preservation of the posterior column vessels during surgery, capsulotomy, and after-treatment. With those precautions, this procedure could be a valid joint-reserving option in treating idiopathic osteonecrosis of the femoral head. TRO is a highly difficult procedure and should be performed only by surgeons who have full training

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