We present our experience of the modified Dunn procedure in combination with a Ganz surgical dislocation of the hip to treat patients with severe slipped capital femoral epiphysis (SCFE). The aim was to prospectively investigate whether this technique is safe and reproducible. We assessed the degree of reduction, functional outcome, rate of complications, radiological changes and range of movement in the hip. There were 28 patients with a mean follow-up of 38.6 months (24 to 84). The lateral slip angle was corrected by a mean of 50.9° (95% confidence interval 44.3 to 57.5). The mean modified Harris hip score at the final follow-up was 89.1 (. sd. 9.0) and the mean Non-Arthritic Hip score was 91.3 (. sd. 9.0). Two patients had proven pre-existing avascular necrosis and two developed the condition post-operatively. There were no cases of nonunion, implant failure, infection, deep-vein thrombosis or heterotopic ossification. The range of movement at final follow-up was nearly normal. This study adds to the evidence that the technique of surgical dislocation and anatomical reduction is safe and reliable in patients with SCFE. Cite this article: Bone Joint J 2013;95-B:424–9

Despite recent advances in the management of slipped capital femoral epiphysis (SCFE), controversy remains about the treatment of choice for unstable slips. Surgical dislocation and open reduction has the advantage of identifying and preserving the blood supply of femoral head thereby potentially reducing the risk of avascular necrosis, (AVN). There is large variation in the literature from several small series about reported AVN rates ranging from two to 66% for unstable SCFE treated with surgical dislocation. The aim of our study was to analyze our experience with acute open reduction and internal fixation of unstable acute and unstable acute on chronic slips using the technique of surgical dislocation described by Professor Reinhold Ganz. A retrospective review of 11 patients (12 hips) treated by surgical dislocation, reduction and pinning as the primary procedure for unstable acute and unstable acute on chronic SCFE in a tertiary referral children's hospital was undertaken. This represents the entire series treated in this manner from September 2007 to January 2018. These procedures were performed by a team of Orthopaedic surgeons with significant experience performing surgical dislocation of the hip including patients with chronic SCFE, Perthes' disease, impingement and acetabular fractures. Demographic data, intraoperative records, postoperative notes and radiographs including details of subsequent surgery were reviewed. There were seven boys and four girls with mean age of 13.4 years, range 11 to 15 years at the time of surgical dislocation. Out of 12 hips, two had acute unstable slip while the remaining 10 had acute on chronic unstable slip. Six patients had good or excellent results. The remaining six patients developed AVN of which three patients had total hip replacement at six months, 17 months and 18 months following primary procedure. Seven patients required more than one operation. Three patients lost their correction and required re fixation despite surgical dislocation, reduction and fixation being their primary procedure. This series demonstrates a high percentage of AVN (50%) in severe unstable SCFE treated with surgical dislocation despite careful attention to retinacular flap development and intra operative doppler studies. This is in direct contrast to our experience with subcapital reorientation with surgical dislocation in stable slips where excellent results were achieved with a low rate of AVN. Pre-operative imaging with MRI and perfusion studies may identify where ischemia has occurred and might influence operative treatment. Based on our results, we do not recommend routine use of surgical dislocation in unstable SCFE. This technique requires further scrutiny to define the operative indications in unstable SCFE

Aims. The aim of this study was to evaluate the efficacy of the surgical dislocation approach and modified trapdoor procedure for the treatment of chondroblastoma of the femoral head. Patients and Methods. A total of 17 patients (ten boys, seven girls; mean age 16.4 years (11 to 26)) diagnosed with chondroblastoma of the femoral head who underwent surgical dislocation of the hip joint, modified trapdoor procedure, curettage, and bone grafting were enrolled in this study and were followed-up for a mean of 35.9 months (12 to 76). Healing and any local recurrence were assessed via clinical and radiological tests. Functional outcome was evaluated using the Musculoskeletal Tumour Society scoring system (MSTS). Patterns of bone destruction were evaluated using the Lodwick classification. Secondary osteoarthritis was classified via radiological analysis following the Kellgren–Lawrence grading system. Steinberg classification was used to evaluate osteonecrosis of the femoral head. Results. The epiphyseal plate was open, closing, and closed in five, five, and seven patients, respectively. In total, eight, six, and three patients were classified as having Lodwick classification IA, IB, and IC, respectively. Allogeneic and autogenous bone grafting was used in 13 and four patients, respectively. All patients had good bone healing and no local recurrence was observed. One patient developed osteonecrosis of the femoral head (Steinberg IA) and one developed secondary osteoarthritis of the hip joint (Kellgren–Lawrence Grade II). The mean postoperative MSTS functional score was 27.7 (24 to 30). Conclusion. Surgical dislocation and modified trapdoor procedures are safe and effective techniques for treating chondroblastoma in the femoral head. Cite this article: Bone Joint J 2019;101-B:732–738

Surgical dislocation of the hip in the treatment of acetabular fractures allows the femoral head to be safely displaced from the acetabulum. This permits full intra-articular acetabular and femoral inspection for the evaluation and potential treatment of cartilage lesions of the labrum and femoral head, reduction of the fracture under direct vision and avoidance of intra-articular penetration with hardware. We report 60 patients with selected types of acetabular fracture who were treated using this approach. Six were lost to follow-up and the remaining 54 were available for clinical and radiological review at a mean follow-up of 4.4 years (2 to 9). Substantial damage to the intra-articular cartilage was found in the anteromedial portion of the femoral head and the posterosuperior aspect of the acetabulum. Labral lesions were predominantly seen in the posterior acetabular area. Anatomical reduction was achieved in 50 hips (93%) which was considerably higher than that seen in previous reports. There were no cases of avascular necrosis. Four patients subsequently required total hip replacement. Good or excellent results were achieved in 44 hips (81.5%). The cumulative eight-year survivorship was 89.0% (95% confidence interval 84.5 to 94.1). Significant predictors of poor outcome were involvement of the acetabular dome and lesions of the femoral cartilage greater than grade 2. The functional mid-term results were better than those of previous reports. Surgical dislocation of the hip allows accurate reduction and a predictable mid-term outcome in the management of these difficult injuries without the risk of the development of avascular necrosis

Residual Legg-Calve-Perthes (LCP) deformities represent one of the most challenging disorders in hip reconstructive surgery. We assessed mid-term PRO. M. s, radiographic correction, complications and survivorship of combined surgical dislocation (SD) and periacetabular osteotomy (PAO) for the treatment of complex LCP deformities. A longitudinal cohort study was performed on 31 hips with complex LCP deformities undergoing combined SD/PAO. Treatment included femoral head reshaping, trochanteric advancement and relative neck lengthening, management of intra-articular lesions and PAO. Twenty-seven (87.1%) had minimum 5-year follow up. Average age was 19.8 years with 56% female and 44% having previous surgery. At a mean 8.4 years, 85% (23/27) of the hips remain preserved (no conversion to THA). The survivorship estimates at 5 and 10 years were 93% and 85%, respectively. The median and interquartile range for mHHS increased from 64 [55–67] to 92 [70–97] (p<0.001), the WOMAC-pain improved from 60 [45–75] to 86 [75–100] (p= 0.001). An additional 19% (n=5) reported symptoms (mHHS <70) at final follow-up. UCLA activity score increased from a median of 8 [6–10] to 9 [7–10] (p=0.207). Structural correction included average improvements of acetabular inclination 15.3. o. ± 7.6, LCEA 20.7° ± 10.8, ACEA 23.4° ± 16.3, and trochanteric height 18 mm ± 10 mm (all, p<0.001). Complications occurred in two (7%) patients including one deep and one superficial wound infection. At intermediate follow-up of combined SD/PAO for complex LCP deformities, 85% of hips are preserved. This procedure provides reliable deformity correction, major pain relief, improved function and acceptable complication/failure rates

Surgical treatment options for Femoroacetabular impingement (FAI) includes both surgical dislocation and hip arthroscopy techniques. The primary aim of this study was to evaluate and compare the survivorship of arthroscopies (scope) and surgical dislocations (SD) at minimum 5-year follow-up. The secondary aim was to describe differences in functional outcomes between the 2 groups. This was a retrospective, single surgeon, consecutive, case-series from a large tertiary care centre. We evaluated all surgeries that were performed between 2005 and 2011. Our institutional database was queried for any patient undergoing surgery for FAI (pincer (n=23), cam (n=306), or mixed (n=103) types). Patients with childhood pathologies i.e. Legg Calve Perthes and slipped capital femoral epiphysis were excluded. This resulted in 221 hips (169 males, 52 females) who underwent either SD (94, 42.5%) or scope (127, 57.5%). A manual chart review was completed to identify patients who sustained a complication, underwent revision surgery or progressed to a total hip arthroplasty (THA). In addition, we reviewed prospectively collected patient reported outcome measure (PROMs) using (SF12, HOOS, and UCLA). Survivorship outcome was described for the whole cohort and compared between the 2 surgical groups. PROMs between groups were compared using The Mann-Whitney U test and the survival between groups was assessed using the Kaplan-Meier Analysis and the Log-Rank Mantel Cox test. All analyses were performed in SPSS (IBM, v. 26.0). The cohort included 110 SDs and 320 arthroscopies. The mean age of the whole cohort was 34±10; patients in the SD group (32±9) were younger compared to the arthroscopy group (39±10) (p<0.0001). There were 16 post-operative complications (similar between groups) and 77 re-operations (more common in the SD group (n=49) due to symptomatic metal work (n=34)). The overall 10-year survival was 91±3%. Survivorship was superior in the arthroscopy group at both 5- (96% (95%CI: 93 – 100)) and 8- years 94% (95%CI: 90 – 99%) compared to the SD Group (5-yr: 90% (95%CI: 83 – 98); 8-yr: 84% (95%CI:75 – 93)) (p=0.003) (Figure 1). On average HOOS improved from 54±19 to 68±22 and WOMAC from 65±22 to 75±22. The improvement in PROMs were similar between the 2 groups. We report very good long-term joint preservation for the treatment of FAI, which is similar to those reported in hip dysplasia. In addition, we report satisfactory improvement in function following such treatment. The differences reported in joint survival likely reflect selection biases from the treating surgeon; more complex cases and those associated with more complex anatomy were more likely to have been offered a SD in order to address the pathology with greater ease and hence the inferior joint preservation identified in this group. For any figures or tables, please contact the authors directly

Surgical dislocation of the hip joint using the technique developed by Rheinhold Ganz, is a relatively new method for surgical exposure of the hip. A review of 8 cases that underwent surgical dislocation of the hip joint was undertaken, to assess the short term outcome, complications associated with the procedure and to identify some of the indications for this technique. This is a retrospective analysis of surgical dislocation in two centers undertaken by the same surgeon with a maximum follow up period of one year. Surgical dislocation of the hip allows access to the hip joint with some associated morbidity due to the surgical exposure but there were no cases of avascular necrosis in the short term follow up. We were able to define specific pathological conditions affecting the hip where there is significant improvement following treatment using this method of exposure of the hip joint. Good exposure of the hip joint is obtained via surgical dislocation so allowing good access for surgical intervention. There is an associated morbidity with the technique but this method of hip exposure allows an alternative to hip arthroscopy and allows easier access to the joint for the treatment of intra articular pathology

Purpose of the study is to investigate the outcome of the patients with Perthes disease who have had a surgical dislocation of their hip for the treatment of resultant symptoms from the disease process. Retrospective review of consecutive patients treated with surgical dislocation of the hip for Perthes disease. Review of clinical case notes and radiological imaging. Patient outcome was assessed at follow-up. Between 2010 and 2015, 31 cases of surgical hip dislocation were performed for Perthes disease at our institution by 2 senior surgeons. Age range at time of surgery was 12–33. Male:female ratio was 13:18; right:left ratio was 15:17. Age at the time of Perthes diagnosis was between 3 and 13 years, with 3 diagnosed retrospectively. Mean follow-up was 18months. All patients had an EUA and arthrogram while 61.3%(19/31) had previous surgery for Perthes. 71%(22/31) required a labral repair, 6.5%(2/31) had a peri-acetabular osteotomy at the time of surgery and 3.2%(1/31) required a proximal femoral valgus osteotomy. 22.5%(7/31) required microfracture (femoral head or acetabulum): all of whom had evidence of contained area of degenerative changes on preoperative MRI. 64.5%(20/31) had the trochanteric screws removed. Complications included 1 greater trochanter non-union, 1 pain secondary to suture anchor impinging on psoas tendon, 1 AVN leading to early THR 12 months post-op. Another 2 had further deterioration of degenerative changes and pain leading to THR 18 and 24 months post-op. All 3(9.7%) had microfracture at the time of the dislocation for established degenerative change and also required custom made prostheses. Surgical hip dislocation is an option in treating Perthes patient with resultant symptoms such as impingement. Improved outcome is seen in patients who are younger with a congruent hip joint in contrast to those with established degenerative change evident on MRI / intraoperatively and have an arrow shaped femoral head

Surgical dislocation of the hip is rarely undertaken. The potential danger to the vascularity of the femoral head has been emphasised, but there is little information as to how this danger can be avoided. We describe a technique for operative dislocation of the hip, based on detailed anatomical studies of the blood supply. It combines aspects of approaches which have been reported previously and consists of an anterior dislocation through a posterior approach with a ‘trochanteric flip’ osteotomy. The external rotator muscles are not divided and the medial femoral circumflex artery is protected by the intact obturator externus. We report our experience using this approach in 213 hips over a period of seven years and include 19 patients who underwent simultaneous intertrochanteric osteotomy. The perfusion of the femoral head was verified intraoperatively and, to date, none has subsequently developed avascular necrosis. There is little morbidity associated with the technique and it allows the treatment of a variety of conditions, which may not respond well to other methods including arthroscopy. Surgical dislocation gives new insight into the pathogenesis of some hip disorders and the possibility of preserving the hip with techniques such as transplantation of cartilage

Introduction: Femoroacetabular Impingement (FAI) with more or less subtle abnormality of the hip anatomy and function may contribute to the early development of osteoarthritis (OA). Surgical dislocation as well as arthroscopy of the hip joint are effective and save tools to correct these anatomic deformities. Good clinical results could be achieved predominantly in patients not exceeding grade I OA. The aim of the presented study was to evaluate the clinical and radiological outcome of patients that were treated by open surgical hip dislocation for more advanced OA of the hip joint (> grade I). Patients and Methods: This is a prospective clinical trial on the outcome of patients after surgical hip dislocation. We report on 45 hip joints (41 patients, 16 m, 25 f) that were treated in our institution by offset-correction (removal of osseous bumps at the femoral head-neck junction) and/or labral surgery for FAI. All patients were evaluated prospectively before and after surgery (Harris Hip Score, radiographic parameters, arthro-MRI). Results: The mean follow up (FU) was 45 months (range: 12–102 months). 9 hips underwent total hip replacement in the further course of FU for persisting pain. In the remaining hips a significant pain reduction but no amelioration of hip range of motion could be accomplished. In 90% of the cases, a good correlation between preop-erative arthro-MRT findings and intraoperative labrum and cartilage assessment could be demonstrated. Concerning the outcome, no patient or radiographic factors could be identified that were strongly associated with failure after surgical dislocation. Discussion and Conclusion: Our data suggests that even patients with more advanced osteoarthritis of the hip may benefit from the surgical dislocation approach as a hip salvage procedure. However, the high number of conversion to total hip arthroplasty indicates, that the indication for hip salvage should stay restricted. Patient or radiographic factors indicative of failure could not be identified. In the future and with more sophisticated molecular MRI techniques such as delayed Gadolinium Enhanced MRI of Cartilage (dGEMRIC) concrete prediction models could be implemented to preoperatively assess hip cartilage in order to sort out patients who will not profit from salvage surgery for advanced OA due to FAI

Complete debridement for synovial chondromatosis of the hip joint is difficult to achieve by standard surgical approaches. The goal of this study was to report preliminary experiences and results for treatment of this disease by a recently developed technique for surgical dislocation of the hip. The technique offers a safe and entire access to the hip joint in order to perform a synovectomy and complete joint debridement. This technique was applied in 8 patients with mean age of 38 years (24–65yrs.). This was done as the initial treatment in 6 patients and for recurrent disease after previous surgery in 2 patients. The mean follow-up was 4.3 years (2–10yrs.). None of the patients had recurrence of synovial chondromatosis. Six of 8 patients showed a good or excellent clinical result without progressive radiographic signs of osteoarthritis (OA). None of the patients developed avascular necrosis. 2 patients underwent total hip joint replacement after 5 and 10 years. One of these two patients had three previous surgeries for recurrence. The other one had the surgical dislocation as initial treatment. Both presented with distinct radiographic signs of OA prior to the index surgery. The technique of surgical dislocation allowed a safe and reliable joint debridement for synovial chondromatosis of the hip. The results indicate that this approach is successful when performed at an early stage without distinct signs of OA

Traumatic posterior dislocation of the hip associated with a fracture of the posterior acetabular wall and of the neck of the femur is a rare injury. A 29-year-old man presented at a level 1 trauma centre with a locked posterior dislocation of the right hip, with fractures of the femoral neck and the posterior wall of the acetabulum after a bicycle accident. An attempted closed reduction had failed. This case report describes in detail the surgical management and the clinical and radiological outcome. Open reduction and fixation with preservation of the intact retinaculum was undertaken within five hours of injury with surgical dislocation of the hip and a trochanteric osteotomy. Two years after operation the function of the injured hip was good. Plain radiographs and MR scans showed early signs of osteoarthritis with some loss of joint space but no evidence of avascular necrosis. The patient had begun skiing and hiking again. The combination of fractures of the neck of the femur and of the posterior wall of the acetabulum hampers closed reduction of a posterior dislocation of the hip. Surgical dislocation of the hip with trochanteric flip osteotomy allows controlled open reduction of the fractures, with inspection of the hip joint and preservation of the vascular supply

Purpose. We share our experience in management of failed in-situ pinning in severe unstable Slipped Capital Femoral Epiphysis (SCFE) by surgical dislocation approach. Method. A retrospective review of hip database from 2006 to 2013 showed 41 children underwent surgical dislocation for SCFE. We identified seven who had severe slip with failed in-situ pinning. Results. The mean age at presentation was 11.9 years (10–14 years). The average interval between in-situ pinning and surgical dislocation was 10 months (2 to 18 months). The mean follow-up was 50.14 months (25 – 66 months). The mean preoperative slip angle in the oblique plane was 76° (61.1° – 121.5°), the mean preoperative alpha angle was 127.3° (93.1° – 145°), and preoperative head neck offset was −12.7mm (0 – −21.2mm). The mean corrections at latest follow-up were oblique plane slip angle 20.6° (4.2° – 41.8°), alpha angle 51.3° (45.3° – 58°), and head-neck offset 9.5mm (1 – 16.2mm). The mean Modified Harris Hip Score (MHHS) preoperatively was 19.57 (0 – 56) and the mean non-arthritic hip score (NAHS) was 21.07 (5 – 51.5). The mean MHHS at the last visit was 88.97 (71 – 96) and NAHS was 84.28 (69.5 – 91). All patients had gross external rotation deformity at presentation; mean internal rotation of 25° ranging from (0 – 40°) was achieved at follow-up. Four patients had avascular necrosis identified on subtraction MRI scan preoperatively. These four underwent second stage hinged distraction of the hip. Mean duration of hinged distraction was 7.6 months. At follow-up 4 had Tonnis 0, one Tonnis 1 and two Tonnis 2 grade of osteoarthritis. Conclusion. The short-term result of our protocol for management of failed in-situ pinning by staged surgical dislocation and hinged distraction has been encouraging. This could potentially prolong the life of native hip to the third decade of life before definitive salvage procedures could be contemplated

Evidence has emerged that femoroacetabular impingement (FAI) may instigate early osteoarthritis of the hip and that symptomatic patients can be successfully treated by addressing the underlying pathomorphology. There is also an increasing body of evidence to support FAI as one major cause of hip and groin pain, decreased mobility and reduced performance in athletes. This study therefore aimed to investigate if professional athletes with FAI can resume to their sports after a surgical dislocation of the hip and continue their professional career up to a mid-term follow-up. We identified fifteen professional athletes (21 hips, all cam-type or mixed-type FAI, mean alpha-angles of 68°) who underwent a surgical hip dislocation for FAI treatment. Surgery was performed by the senior author in all cases. The patients were evaluated by postal survey at a mean of 47 months (range, 9–79) postoperatively. The evaluation inquired about the type and level of sports, subjective ratings, and clinical outcomes (Hip Outcome Score [HOS], SF-12, UCLA activity scale, FAI sports scale [FSS], VAS pain). At follow-up, 14 of the 15 patients (93%) were still professionally sports active. Twelve athletes maintained their levels and two were active in minor leagues. Eleven patients (75%) were satisfied with their hip surgery and their sports ability. Mean activity levels were 7.5 according to the self-developed FSS and 9.7 according to the UCLA scale, respectively. Mean scores of the HOS ADL and Sport subscales were 92.6 and 85.2, respectively. Mean scores of the SF-12 PCS and MCS were 50.7 and 56.1, respectively. Pain levels during sports were rated to be 2.0 according to the VAS. In conclusion, this study highlighted that professional athletes suffering from FAI can successfully return to professional sports after a surgical dislocation of the hip. All athletes except one (93%) could continue their professional career up to the follow-up four years after surgery. Clinical outcomes in terms of subjective ratings and scores were encouraging, nevertheless, longer-term follow-up has to show if results deteriorate with time considering the exhaustive joint use related to a professional sports career

Introduction: Percutaneous in situ pinning of severe SUFE can lead to problems. We describe our technique and results for surgical dislocation to reduce severe SUFE. Method: Ganz’s approach of greater trochanteric flip, safe dissection and surgical dislocation to preserve the femoral head blood supply was followed to anatomically reduce the femoral head. We have treated 16 cases in this way, but describe nine with a minimum follow up of 2 years. Their mean age was 13.6 years (9 to 16 years). All had severe SUFE with four acute on chronic and two unstable slips. Two were previously pinned and another had a partially fused growth plate. The mean follow up was 3.1 years (2.1 to 4.6 years). Results: All patients had a good to excellent outcome. Their pre-operative deformity was 84 degrees (65 to 110) measured by AP and cross table lateral x-rays, CT or MRI scans. The average hip external rotation deformity was 70 degrees. Post operatively internal and external rotation and all other movements were similar to the contra-lateral uninvolved hip. None developed avascular necrosis (AVN) or chondrolysis. Conclusions: This technique is demanding but can give good results for severe SUFE

Purpose: Unstable slipped capital femoral epiphysis (SCFE) can result in a high incidence of avascular necrosis (AVN) and residual deformity leading to femoral acetabular impingement (FAI). Surgical hip dislocation with open reduction and internal fixation (ORIF) has been proposed as a surgical method to avoid or limit these complications. Method: A prospective consecutive series of patients who presented with an unstable SCFE and underwent a surgical hip dislocation/ORIF were reviewed. The procedure entails urgent arrival to the operating room, a surgical dislocation procedure to gain full access to the proximal femur, removal of the posterior and medial callus with necessary shortening of the femoral neck to anatomically reduce the femoral head without tension on the vasculature. Results: There are 15 patients in this series with a minimum of 1 year follow-up. Average age was 12.5 years at the time of presentation, 10 males and 5 females. Surgical dislocation was performed at a mean of 29.1 hours from the traumatic event. The surgical procedure averaged 135.5 minutes, with an average blood loss of 220ccs. Fourteen patients have no evidence of AVN while one patient with AVN was due to a surgical step not performed in the remaining hips. Normal anatomic position of the epiphysis was achieved in 11 of 15 patients while the remaining 4 had mild posterior angulation averaging 6.2 degrees. Average hip flexion was 114°, internal rotation 22°, external rotation 35°. Two patients required reoperation for broken screws (both 4.5mm cannulated screws). Conclusion: Surgical dislocation with removal of medial and posterior callus and shortening of the femoral neck can reduce the femoral head to a near anatomic position to avoid FAI and appears to result in a very low incidence of avascular necrosis. A single patient with AVN was the result of technical issue which can be avoided

Femoroacetabular impingement (FAI) is a pathologic condition of the hip joint that leads to hip pain and osteoarthrosis (OA), especially in the young and active patient population. It is characterized by an early pathologic contact during hip motion between osseous malformation of the femoral neck and acetabular rim. The goal of the surgical dislocation of the hip is to prevent the development of OA by correcting these malformations. We investigated the clinical and radiographic outcome, the survivorship, and factors predicting poor outcome at 5-year followup. We retrospectively evaluated 101 hips in 78 patients that underwent surgical hip dislocation at a mean age of 32 ± 8.4 (range, 15 – 52) years. The mean followup was 5.7 ± 1.0 (0.9 – 7.1) years. The series included pincer type impingement in 5 hips (5%), cam type in 9 hips (9%), and mixed type of FAI in 87 hips (87%). Pre-operatively, the patients presented with a mean Merle d’Aubigné score of 14.3 ± 3.3 (8 – 17) and a mean osteoarthrosis score according to Tönnis of 0.13 ± 0.34 (0 – 1). At followup, the clinical results were graded using the Merle d’Aubigné score and the radiographic results using the Tönnis score. Failure was defined as a conversion to a total hip arthroplasty (THA), a Merle d’Aubigné score of less than 15 or a progression of osteoarthrosis with a Tönnis score ≥2 at last followup. Demographic, clinical, radiographic, and surgical factors were tested for predictive factors for poor outcome using the Cox regression. At followup the mean Merle d’Aubigné score was 17.2 ± 1.2 (12 – 18) and the mean Tönnis score was 0.19 ± 0.47 (0 – 2). Failures (13 hips, 13%) included 6 hips (6%) with a progression of osteoarthrosis, 5 hips (5%) hips that converted to a THA, and 2 (2%) hips presenting with a Merle d’Aubigné score of less than 15. This resulted in a cumulative survivor ship at 5 years of 97.0 ± 3.3 % (95%-confidence interval, 93.6 – 100%). Factors predicting poor outcome were a preoperative Tönnis score of 1, a cartilage tear in the Arthro-MRI, and increased age or BMI at operation. Surgical hip dislocation has the potential to prevent the progression of osteoarthrosis and to decrease hip pain in patients with FAI. The optimal patient is young, with a decreased BMI and no sign of degeneration in the conventional radiograph or Arthro-MRI

Femoroacetabular impingement (FAI) is the result of abnormal contact/impingement of the femoral head-neck junction and acetabulum during motion. This can be corrected by surgical dislocation (using Ganz's trochanteric osteotomy) and femoral osteochondroplasty +/− acetabular rim resection. Our study aimed to assess the improvement in hip scores following open osteochondroplasty to predict outcomes based on patient characteristics. This was a retrospective case note analysis of a single surgeon case series over a 4 year period. Inclusion criteria were open osteochondroplasty, complete pre- and post-op hip scores available), Tonnis osteoarthritis grade 0 or 1, with 1 year followup. Data was extracted from electronic and paper case notes for pre- and post-op Modified Harris Hip Scores (MHHS), Non-arthritis Hip Scores (NAHS) and SF-12 general satisfaction scores, as well as baseline patient demographics. Two independent observers used the PACS radiology system to examine x-rays and MRI. SPSS version 19 was used for statistical analysis. 42 patients met the inclusion criteria. There was an overall improvement in hip scores after the procedure. Mean pre-op scores were MHHS 52.5, NAHS 44.0, SF-12 32.1. Mean post-op scores were MHHS 66.1, NAHS 58.7, SF-12 36.4. Therefore mean improvements were seen in MHHS (13.6), NAHS (14.7) and SF-12 (4.3), all significant at p<0.005 when paired t-test was used for analysis. Pearson correlation for subgroup analysis showed no significant correlation of scores with age, centre-edge angle or alpha angles. Furthermore, no significant difference was seen between males and females (independent t test). Open osteochondroplasty improves symptoms and function based on patient reported outcome measures. Although the mean scores improved, some patients’ scores deteriorated. We have not identified any statistically significant predictors of outcome, and therefore patient selection remains unclear

We report our early Boston experience with the technique of Ganz, et al., for surgical dislocation of the hip, which provides a safe, powerful approach to certain major intraarticular hip problems. Materials and Methods: Forty-seven hips with various mechanical disorders have been treated using the Ganz technique of trochanteric flip osteotomy and anterior dislocation (JBJS 83-B: 1119-1124, 2001). Diagnoses include slipped epiphysis 14, Perthes 12, aspherical head/ anterior offset 12, dysplasia 14, multiple exostoses 2, other 3.Seven patients had simultaneous femoral oste-otomies; four had subcapital osteotomies for epiphys-iolysis. All patients had pain and limitation of motion preoperatively, and more than fifty percent had severe deformity and/or some arthrosis. Follow-up was six months to five years. Ages at surgery were eight to forty-eight years (mean twenty years). Results: The variety of pathologies render objective analysis difficult, though all patients reported greatly reduced pain and increased motion post operatively. Only five patients were totally pain free and had objectively totally normal hips. No patient felt unimproved. No patient had radiographic signs of osteonecrosis. Conclusion: Paralleling the Bernese experience of more than eight hundred cases, we find the Bernese technique of surgical dislocation to be a safe, effective tool for treating intra-articular hip pathology, increasing treatment possibilities for hip joint preservation. We anticipate greatly expanding its use in the future

Introduction. We present a single surgeon series of 20 modified Dunn osteotomies without surgical dislocation of the femoral head for slipped upper femoral epiphysis (SUFE). Method. All patients from 2007 to 2011 who had a Dunn osteotomy for SUFE had their notes reviewed and we obtained an updated Non Arthritic Hip Score. Results. 20 patients were identified, of which 5 were female, with a combined average age of 14. The average duration of symptoms prior to the procedure was 10.2 weeks (range, 4–78). Classifications divided the cases into 7 chronic slips, 7 acute-on-chronic, and 5 acute., and 7 of the cases were unstable slips with an average slip angle of 71 degrees (range 65–85). All slips were grade 3. Average follow up was 26.2 months (range, 2–62). 3 developed avasular necrosis (2 unstable, 1 stable) and 2 patients had symptomatic leg length discrepancy. Preoperative MRI scans were performed in 4 patients and showed vascular compromise, but this did not always correlate with intraoperative findings of avascularity when the head was drilled. The average Nonarthritic hip score was 71.6 (range, 60–80). Summary. Dunn osteotomies are safe in patients with chronic slips, and have a low incidence of AVN. Overall function was good, even in those patients with segmental AVN scoring highly on their hip scores. Keeping the ligamentum teres intact and not dislocating the femoral head may improve vascularity of the head. Vascularity may also be assessed by preoperative MRI scans, although radiological suggestion of an avascular head which contradicted clinical findings and postoperative outcome may be due to transient vessel spasm