Recently, there has been a reluctance to perform hip arthrodesis. The number of patients requiring the conversion from hip arthrodesis to arthroplasty has also decreased. We present the functional results following conversion of hip arthrodesis to total hip arthroplasty at a specialist hip centre. 76 patients who underwent conversion of hip arthrodesis to total hip arthroplasty between 1963 and 2000 at the Centre for Hip Surgery, Wrightington Hospital, were included in this retrospective study. 9 patients died of unrelated causes and 7 patients were lost to follow up. The functional scoring was performed using the Merle d’Aubigné and Postel score. The mean age at the time of surgical hip arthrodesis was 16.7 years and at the time of conversion was 48.7 years. Back pain is the most common indication for the conversion. All the patients were pleased with the clinical outcome following conversion to Arthroplasty. 6 patients had postoperative complications. The mean Merle d’Aubigné and Postel score increased from 8.97 to 13.46 at the latest follow-up. The mean wear rate was 0.06 mm/year. Survival of hip arthroplasty was 92.78 % at 18 years. Conclusion: Our series demonstrates good outcome and patient satisfaction and high survival of the arthroplasty following the conversion from arthrodesis. Hip arthrodesis could be considered as a holding procedure in selected group of young patients with a later successful conversion to arthroplasty

The main challenges in hip arthrodesis takedown include the decision to perform fusion takedown and the technical difficulties of doing so. In addition to the functional disadvantages of hip fusion, the long-term effects of hip arthrodesis include low back pain and in some cases ipsilateral knee pain. Indications for fusion conversion to THA include arthrodesis malposition, pseudoarthrosis, and ipsilateral knee, low back, contralateral hip problems, and functional disadvantages of ipsilateral hip fusion. When deciding whether or not to take down fusion, consider the severity of the current problem, risks of takedown and likely benefits of takedown. Best results of fusion takedown occur if abductor function is likely to be present. If the abductors are not likely to function well, dearthrodesis may still help, but the patient will have a profound Trendelenburg or Duchenne gait and risk of hip instability will be higher. Abductor assessment can be performed by determining if the abductors contract on physical exam and determining if the previous form of fusion spared the abductors and greater trochanter. EMG and MRI also can be performed to assess the abductors, but value in this setting is unproven. Before dearthrodesis establish realistic expectations: most patients will gain hip motion—but not normal motion, most will see improvement in back/knee pain, but many will become cane-dependent for life. The main technical issues to overcome involve exposure, femoral neck osteotomy, acetabular preparation, and femoral fixation. Exposure can be conventional posterior, anterolateral or direct anterior with an in-situ femoral neck cut. In complex cases, a transtrochanteric approach is often helpful. The in-situ neck cut is facilitated by fluoroscopy or intraoperative radiograph to make sure the cut is at the correct level and at the correct angle. Be careful not to angle into the pelvis with the cut. Acetabular preparation is more complex because anatomic landmarks often are absent or distorted. Try to find landmarks including ischium, ilium, teardrop, and fovea. Confirm location with fluoroscopy as reaming commences and during reaming. Depth of reaming can be improved by using the fovea (if present) and teardrop on fluoroscopy. Cup fixation is usually an uncemented cup, fixed with multiple screws because bone quality typically is compromised. Femoral fixation is at the surgeon's discretion, recognizing the proximal bone may be distorted in some cases. Postoperative management includes protected weight bearing as needed and heterotopic bone prophylaxis in selected patients

Introduction. Hip Arthrodesis had been considered as a useful surgical option in young adult patient with high activity demands suffering from osteoarthritis of the hip. Although the procedure surely eliminates pain of the hip joint, it can also cause disorders of the adjacent joints in addition to the complete loss of motion, might consequently deteriorate the activity of daily living. The purpose of this retrospective study was to investigate the efficacy and drawback of hip arthrodesis, focusing on the effect of this procedure on the adjacent joints. Materials and Methods. From 1976 to 1989, 29 hip arthrodesis were performed and 22 hips were followed up (1 died, 6 lost). Disorders led to arthrodesis were septic arthritis (1 hip), post-traumatic (1), osteonecrosis (1), primary osteoarthritis (3), and secondary osteoarthritis due to DDH (16). The average age at surgery was 38 years (range, 19–53 years, 6 men and 16 women). Hip arthrodesis was indicated for young active adults with end stage osteoarthritis, who had normal or mild osteoarthritis in contralateral hip and needed physical labor. The hip was positioned in 30 degrees of flexion, 0 to 5 degree of external rotation, and 0 to 5 degree of abduction. Clinical and radiographic assessment was done for these patients. The clinical follow-up consisted of questionnaire which assessed ability of typical Japanese daily living movement and patient's satisfaction. The condition of the adjacent joints was evaluated clinically and radiographically. Results. After an average follow-up of 22 years (range15-28), no patients complained of pain in the fused hip joint. On the other hand, pain in the adjacent joints was seen frequently. Seventeen (77%) of 22 patients had low back pain and one of these patients, who had severe low back pain, required conversion of arthrodesis to THA. Ten patients (45%) had contralateral hip pain and 8 (36%) of whom subsequently needed THA. All patients who required THA had early stage osteoarthritis when they underwent arthrodesis. Ten patients (45%) had knee pain (5 in the ipsilateral and 5 in the contralateral knee). Radiographic progression of osteoarthritis in adjacent joints was also seen frequently, namely, 9 in lumbar spine, 11 in contralateral hip, 6 in ipsilateral and 6 in contralateral knee. Although pain in the involved hip disappeared, activity of daily living was severely deteriorated (impossible to clip nail: 88%, ride a bicycle: 94%, use a Japanese toilet: 75%, sit in Japanese style: 50%). As a result, only 4 patients (18%) were satisfied with the hip arthrodesis. Discussion. The satisfaction of hip arthrodesis was unexpectedly poor despite of pain relief of involved hip joint. One of essential reasons was activity of daily living in Japanese style, which requires relatively deep flexion in hip and knee. Compensation of limited movement in hip might cause pain and progression of osteoarthritic change in adjacent joints. Another vital reason was that we indicated this procedure for bilateral DDH case whose contralateral hip had early stage osteoarthritis, ended up with THA in most cases

Introduction. Management of the sequelae of arthritis of the hip joint has changed over time. Total joint replacement has gained popularity due to retained mobility and stability. In the high demand paediatric and adolescent population problems are encountered with longevity of the procedure. Hip arthrodesis is a useful alternative procedure that sacrifices mobility of the joint to achieve pain relief and restores function. Several surgical techniques have been described to achieve hip fusion. We describe a technique that achieves concentric bone surfaces with hip resurfacing reamers. Maximum bone is preserved to maintain leg length. Trans-articular compression is achieved with cannulated screw fixation. Subtrochanteric de-functioning osteotomy completes the procedure to protect the fusion site and control the position of the limb. Our optimal position of fusion was 30 degrees of flexion, neutral to 5 degrees of abduction and neutral to 10 degrees of external rotation. Methods. Fourteen patients (8 female) treated by hip arthrodesis over a two-year period are reviewed in terms of clinical and radiological outcome in the short term. Their mean age at hip fusion was 11 years (6–18). The etiology included TB (6 cases), staphylococcal infection (2), non-specific arthritis (3), Perthe's (1), chondrolysis (1) and avascular necrosis following trauma (1). Results. Fusion was achieved in 12/14 patients. All patients in whom fusion was achieved had relief of pain and returned to their normal activities. Conclusion. We believe hip arthrodesis performed in the correct patient is a good procedure to preserve function and relieve pain. The procedure is technically demanding and careful follow-up to ensure optimal positioning and solid fusion is essential to ensure good results. NO DISCLOSURES

Patients with longstanding hip fusion are predisposed to symptomatic degenerative changes of the lumbar spine, ipsilateral knee and contralateral hip. 1. In such patients, conversion of hip arthrodesis to hip replacement can provide relief of such symptoms. 2 – 4. However, this is a technically demanding procedure associated with higher complication and failure rates than routine total hip replacement. The aim of this study was to determine the functional results and complications in patients undergoing hip fusion conversion to total hip replacement, performed or supervised by a single surgeon. Twenty-eight hip fusions were converted between 1996 and 2016. Mean follow up was 7 years (3 to 18 years). The reasons for arthrodesis were trauma 11, septic arthritis 10, and dysplasia 7. The mean age at conversion was 52.4 years (26 to 77). A trochanteric osteotomy was performed in all hips. Uncemented components were used. A constrained liner was used in 7 hips. Heterotopic ossification prophylaxis was not used in this series. HHS improved a mean of 27 points (37.4 pre-op to 64.3 post-op). A cane was used in 30% of patients before conversion and 80% after. Heterotopic ossification occurred in 12 (42.9%) hips. There was 2 peroneal nerve injuries, 1 dislocation, 1 GT non-union and 1 infection. There have been 5 revisions; 2 for aseptic loosening, 1 for infection, 1 for recurrent dislocation and 1 for leg length discrepancy. Conversion of hip fusion to hip replacement carries an increased risk of heterotopic ossification and neurological injury. We advise prophylaxis against heterotropic ossification. When there is concern about hip stability we suggest that the use of a constrained acetabular liner is considered. Despite the potential for complications, this procedure had a high success rate and was effective in restoring hip function

We report an intertrochanteric fracture in a patient who had undergone hip arthrodesis 30 years previously. A 53-year-old man was injured in a head-on car crash and was referred to our hospital for treatment. Plain radiographs showed an intertrochanteric fracture of the right proximal femur and deformity of the right hip joint. He had undergone hip arthrodesis surgery 30 years previously at another hospital. Computed tomography scan showed marked atrophy of the gluteus and iliopsoas muscles. He preferred undergoing total hip arthroplasty (THA) to internal fixation. THA was performed using the anterolateral approach with the patient in the supine position as he had undergone hip arthrodesis through the Smith–Petersen approach, and we were concerned about damaging the gluteus muscle and dislocation if we took the posterolateral approach. The femoral head was removed using curved chisels under fluoroscopy. A cementless THA (J Taper stem, Aquala polyethylene liner; Kyocera Medical Corporation, Osaka, Japan) was inserted and fixed appropriately. Full weight-bearing using a walking frame was allowed 2 weeks after the surgery. Six months after the operation, he was able to walk independently and had good range of movement of the hip joint but continued to have weakness in the abductor muscles. Very few cases of proximal femur fracture in a previously arthrodesed hip have been reported. Manzotti et al. reported a similar case but they performed open reduction and internal fixation. No previous reports in the literature describe THA for intertrochanteric fracture in an arthrodesed hip. The conversion of an arthrodesed hip to THA is technically challenging. It has a high risk of complications such as nerve injuries and hip instability. We were able to treat the patient successfully, but surgeons should carefully decide the treatment method depending on the case

Introduction: The management of young adults with severe osteoarthritis of the hip still remains a problem because of the increased failure rates of total hip arthroplasty in this active high demanding individuals. Hip arthrodesis if done with proper patient selection and proper arthrodesis position provide a viable alternative with good functional results. Objective: The objective of our study was to review the functional outcome after hip arthrodesis and to review its implications on patientñs general life. Material & methods: In our retrospective study we reviewed thirteen patients (5 males,8 females) who had hip arthrodesis at an average age of 30 years. Indications include Septic arthritis, T.B, A.V.N and osteoarthritis secondary to trauma. Cobra Head plate Technique was used. The mean follow up was 15.2 years. All cases had union at the time of followup. SF 36 and Modiþed Harris hip score was used to assess the functional outcome. Isokinetic muscle strength was measured using Cybex machine. Results: Solid arthrodesis was noted in all cases at follow-up. 50% of cases complained of back pain and only one patient complained about ipsilateral knee pain. The average Haris hip score was 76. The average deþcit in extension torque in the involved leg was 46% and average deþcit in ßexion torque was 4%. The differences in torque were compared using a t-test and extension difference was found to be statistically signiþcant (p< 0.0001). Female patients did well as well as male patients with 70% having no major difþculties in sexual relationship. Ten out of 13 were satisþed with the operation but 7 of 13 would undergo it again given the alternative of total joint arthroplasty. Conclusion:We conclude that hip arthrodesis is still a viable alternative procedure in carefully selected patients

The main challenges in hip arthrodesis takedown include the decision to perform fusion takedown and the technical difficulties of doing so. In addition to the functional disadvantages of hip fusion, the long-term effects of hip arthrodesis include low back pain and in some cases ipsilateral knee pain. Indications for fusion conversion to THA include arthrodesis malposition, pseudoarthrosis, and ipsilateral knee, low back, contralateral hip problems, and functional disadvantages of ipsilateral hip fusion. When deciding whether or not to take down a fusion, consider the severity of the current problem, risks of takedown and likely benefits of takedown. Best results of fusion takedown occur if abductor function is likely to be present. If the abductors are not likely to function well, dearthrodesis may still help, but the patient will have a profound Trendelenburg or Duchenne gait and risk of hip instability will be higher. Abductor assessment can be performed by determining if the abductors contract on physical exam and determining if the previous form of fusion spared the abductors and greater trochanter. EMG and MRI also can be performed to assess the abductors, but value in this setting is unproven. Before dearthrodesis establish realistic expectations: most patients will gain hip motion—but not normal motion, most will see improvement in back/knee pain, but many will become cane-dependent for life. The main technical issues to overcome involve exposure, femoral neck osteotomy, acetabular preparation, and femoral fixation. Exposure can be conventional posterior, anterolateral or direct anterior with an in situ femoral neck cut. In complex cases, a transtrochanteric approach is often helpful. The in situ neck cut is facilitated by fluoroscopy or intra-operative radiograph to make sure the cut is at the correct level and at the correct angle. Be careful not to angle into the pelvis with the cut. Acetabular preparation is more complex because anatomic landmarks often are absent or distorted. Try to find landmarks including ischium, ilium, teardrop, and fovea. Confirm location with fluoroscopy as reaming commences and during reaming. Depth of reaming can be improved by using the fovea (if present) and teardrop on fluoroscopy. Cup fixation is usually an uncemented cup, fixed with multiple screws because bone quality typically is compromised. Femoral fixation is at the surgeon's discretion, recognizing the proximal bone may be distorted in some cases. Post-operative management includes protected weight bearing as needed and heterotopic bone prophylaxis in selected patients

Aim. To compare the functional outcome of proximal femoral reconstruction using endoprosthetic replacement and hip arthrodesis using a vascularised fibular graft. Material and Methods. The study included thirty-five patients who had proximal femoral reconstruction following resection of a malignant bone tumour. Patients were divided into 2 groups according to the reconstructive modality used. Group 1 (15 patients) reconstructed by hip arthrodesis using a vascularised fibular graft. Group 2 (20 patients) reconstructed by endoprosthesis. The mean age of group I was 14.9 years (range, 7-25). 8 patients had Ewing's sarcoma, 5 osteogenic sarcoma, and 2 chondrosarcoma. In group 2, the mean age was 35 years (range, 14-61). Eight patients had osteogenic sarcoma, 2 chondrosarcoma, 2 Ewing's sarcoma, 1 lymphoma, 1 MFH, 1 synovial sarcoma, 1 parosteal osteosarcoma, and 4 metastatic carcinomas. Results. In group 1 failure of the fixation occurred in two patients, and deep infection developed in one patient. These patients were managed with revision of internal fixation and debridement respectively. The mean MSTS functional score was 87% (range 70 – 96%) at the time of the latest follow-up (mean = 64 months). The average limb length discrepancy was 2 cm (range 1 to 4). In group 2, two patients developed deep infection, one patient had a dislocation, and one had loosening of the implant with a re-operation rate of 20%. After a mean follow up of 49.1 months, the mean MSTS functional score was 79% (range 60 – 93%). Conclusion. The functional outcome of hip arthrodesis using a vascularized fibular graft is comparable to endoprosthetic replacement after proximal femoral resections. It should be considered as a durable reconstructive modality in children and young active patients with long life expectancy

Aims

The aim of this study was to evaluate the suitability of the tapered cone stem in total hip arthroplasty (THA) in patients with excessive femoral anteversion and after femoral osteotomy.

Fifteen patients (11 males, 4 females) with a median age of 16 years (range, 7–25) were treated in our centre by intra-articular resection of the proximal femur, and hip arthrodesis using a vascularized fibular graft. Eight patients had Ewing’s sarcoma, 5 osteogenic sarcoma, and 2 chondrosarcoma. After a mean follow up of 58.2 months, 13 patients were alive with no evidence of disease. All fibular grafts united at a mean time of 7.6 months (range, 7–9 months). Four patients had stress fractures of the vascularized fibular graft, all healed after a mean period of 6.5 weeks. Failure of the fixation system occurred in two patients. Deep infection developed in one case which necessitated plate removal. Three of these patients with complications underwent a second procedure, giving a re-operation rate of 20%. The mean MSTS functional score was 85.9% at the time of the latest follow-up. We conclude that hip arthrodesis using a vascularized fibular graft is a viable alternative to endoprosthetic replacement after proximal femoral resections. It should be considered as an effective and durable reconstructive technique in young patients with high physical demands

Purpose: A modification of the arthrodesis as described by F R Thompson is reviewed in ten children. Method: Between September 1997 and July 2001, six patients ranging from 6 to 13 years underwent hip arthrodesis. Indications included trauma (one), idiopathic chondrolysis (one) post-septic arthritis (four) and tuberculosis of the hip joint (four). The subtrochanteric osteotomy was performed as a coronal chevron, differing from the previously described techniques. Patients were immobilized in a spica (six) and external fixation (four) in a functional position of 20 degrees flexion and neutral position (1degree abduction per year of growth left) for six weeks postoperatively. Conclusion: This review re-establishes hip arthrodesis as an acceptable treatment for children with destroyed joints and intractable pain. The modification used provides an attractable alternative in preventing the displacement of the subtrochanteric osteotomy, but allows correct positioning of the limb. The use of the external fixation allows lengthening if needed

Between September 1997 and April 2000 hip arthrodesis was performed on six patients, using a modification of the techniques described by F.R. Thompson. The ages of patients ranged from 11 to 13 years, and indications included trauma (one patient) post-septic arthritis (two patients) and tuberculosis of the hip joint (three patients). The subtrochanteric osteotomy was performed as a coronal chevron, differing from previously described techniques. Patients were immobilised in a spica in a functional position of 20° flexion and the zero position (1° abduction per year of growth left) for six weeks postoperatively. The follow-up period ranged from 16 to 40 months. Union was achieved within six weeks. All patients achieved a pain-free gait, with minimal signs of disability. We believe that hip arthrodesis is an acceptable way of treating children with destroyed joints and intractable pain. The modification we used prevents displacement of the sub-trochanteric osteotomy but allows correct positioning of the limb

Hip arthrodesis is still a major option for the painful arthritic hip in the third world, where total hip prostheses are seldom available or too expensive for the patient. Various procedures for hip fusion have been described in the literature; they are often complex, frequently need a long period of post-operative immobilisation and are coupled with a considerable failure rate. A new simple technique for hip arthrodesis is described without dislocating the hip preoperatively in order to maintain the oxygen concentration in the femoral head, using a self devised plate and requiring no post-operative immobilisation. During a three year period the procedure was performed in 22 patients by the same surgeon. In all cases the indication for hip fusion was hip osteo-arthritis. The cause of osteo-arthritis was in 46% hip destruction by tuberculosis, in 23% aseptic osteonecrosis of the femoral head, mostly linked to sickle cell anaemia, in 8% complications of trauma of the hip, in 8% slipped upper femoral epiphysis and in 15% primary arthritis. Two had concurrent femoral osteotomy for correcting malposition of the limb and one had during the same procedure a femoral diaphysis osteotomy with placement of a Wagner elongating device in order to proceed with a callotasis. Mean follow up was 15.4 months. All hips, except one, achieved a solid fusion by radiographic and clinical criteria between 6 and 12 months after surgery. The failure of fusion was in the oldest patient (63 years) who presented loosening of plate and screws due to an advanced degree of osteoporosis. One superficial infection occurred that resolved under antibiotics

The modified Dunn procedure has the potential to restore the anatomy in hips with slipped capital femoral epiphyses (SCFE) while protecting the blood supply to the femoral head. However, there is controversy about the risks associated with the procedure especially in the most severe capital slips. Therefore, we report on (1) clinical outcome, (2) the cumulative survivorship with endpoints AVN and/or OA progression and (3) radiographic anatomy of the proximal femur at followup in patients treated with a modified Dunn procedure for severe SCFE. We performed a retrospective analysis involving 46 hips of 46 patients treated with a modified Dunn procedure for severe SCFE (slip angle >60°) between 1999 and 2016. Followup averaged 8 years, (range 1–17) with 2 patients lost to followup after one year. The mean age was 13 years (range 9–19 years). Mean preoperative slip angle was 64° (range 60–90) and 14 out of 46 hips (30%) presented with unstable slips. Clinical scores and PROMs were evaluated and the hips were followed standard x-rays. Cumulative survivorship (Kaplan-Meier) with three defined endpoints: (1) AVN; (2) progression by at least one OA grade according to Tönnis; (3) non-preserved hip joint. (1)Mean Harris Hip score (HHS) was 93 points (66–100) and mean Hip Disability and Osteoarthritis Outcome Score (HOOS) was 90 points (67–100) at last followup. (2)Cumulative survivorship was 93% at 10-year followup. Three hips reached an endpoint. Two hips (4%) had AVN, one of them underwent hip arthrodesis. One hip had OA progression. (3)Postoperative slip angle was 7° (1–16). Alpha angle on axial radiograph was 39° (26–71) at followup. 41/44 hips (93%) had no OA (Tönnis 0). The modified Dunn procedure largely corrected slip deformities with low apparent risk of progression to avascular necrosis or osteoarthritis at mean 8-years followup. The AVN rate in severe and unstable (30%) capital slip was 4% (2 hips) with this procedure

Patients with longstanding hip fusion are predisposed to symptomatic degenerative changes of the lumbar spine, ipsilateral knee and contralateral hip. In such patients, conversion of hip arthrodesis to hip replacement can provide relief of such symptoms. However, this is a technically demanding procedure associated with higher complication and failure rates than routine total hip replacement. The aim of this study was to determine the early functional results and complications in patients undergoing hip fusion conversion to total hip replacement, performed or supervised by a single surgeon, using a standardised approach and uncemented implants. We hypothesised that a satisfactory functional improvement can be achieved in following conversion of hip fusion to hip replacement. Eighteen hip fusions were converted to total hip replacements. A constrained acetabular liner was used in 3 hips. Mean follow up was 5 years (2 to 15 years). Two (11%) hips failed, requiring revision surgery and two patients (11%) had injury to the peroneal nerve. Heterotopic ossification developed in 7 (39%) hips, in one case resulting in joint ankylosis. No hips dislocated. Conversion of hip fusion to hip replacement carries an increased risk of heterotopic ossification and neurological injury. We advise prophylaxis against heterotopic ossification. When there is concern about hip stability we suggest that the use of a constrained acetabular liner is considered. Despite the potential for complications, this procedure had a high success rate and was effective in restoring hip function

Some DEFINITIONS are necessary: “STEMS” refers to “intramedullary stem extensions”, which may be of a variety of lengths and diameters, fixed with cement, porous coating or press fit alone and which may be modular or an inherent part of the prosthesis. The standard extension keel on the tibia does not qualify as a “stem (extension)”. COMPLEX implies multiple variables acting on the end result of the arthroplasty with the capability of inducing failure, as well as necessary variations to the standard surgical technique. A lesser degree of predictability is implied. More specifically, the elements usually found in an arthritic knee and used for the arthroplasty are missing, so that cases of COMPLEX primary TKA include: Soft tissue coverage-(not relevant here), Extensor mechanism deficiency-patellectomy, Severe deformity, Extra-articular deformity, Instability: Varus valgus, Instability: Plane of motion, Instability: Old PCL rupture, Dislocated patella, Stiffness, Medical conditions: Neuromuscular disorder, Ipsilateral arthroplasty, Prior incisions, Fixation hardware, Osteopenia, Ipsilateral hip arthrodesis, Ipsilateral below knee amputation, etc. Complexity includes MORE than large deformity, i.e., success with large deformity does NOT mean success with constrained implants regardless of indication. In addition, the degree of constraint must be specified to be meaningful. NECESSARY presumably this means: “necessary to ensure durable fixation in the face of poor bone quality or more mechanically constrained” and SUFFICIENT suggests that stems, by themselves or in some shape of form, by themselves “will ensure success (specifically here) of fixation”. If we can start with the second proposal, that STEMS are SUFFICIENT for success the answer is: “NO”, many more aspects of surgical technique and implant design are required. Even if all other aspects of the technique are exemplary, some types of stems or techniques are inadequate, e.g., completely uncemented, short stem extensions. The answer to the first proposal is: “YES, in many cases”. The problem will be to determine which cases. There are philosophical analogies to this question that we already know the answer to. ANALOGY: Is a life-raft necessary on a boat? Yes, you may not use it, but it is considered necessary. Is a life-raft “sufficient” on a boat? No, other problems may occur. Are seat belts necessary? Are child seats necessary? The AAOS already has a position on child restraints, an analogous situation, where a party who cannot control their situation (anesthetised patient/ child) functions in the care of a responsible party. The objection may be argued in terms of cost saving by NOT using increased fixation. A useful analogy, (that would of course require specific analysis), is that of patellar resurfacing: universal resurfacing is cost-effective when considering the expense of even a small number of secondary resurfacings. Of course a complex arthroplasty that requires a revision procedure is far more expensive than secondary patellar resurfacing and so universal use of the enhanced fixation in the face of increased constraint makes sense. The human cost of revision surgery tips the balance irrefutably. DANGER-We must avoid the glib conclusion, often based on poor quality data, that constrained implants do not need additional intramedullary fixation (with stem extensions). When “complexity” is involved, complex analysis is appropriate to select the best course

Introduction: Avascular necrosis (AVN) is a devastating complication of slipped capital femoral epiphysis (SCFE) and is difficult to treat. The incidence of AVN in this condition varies considerably and is reported to appear in 3–47% of patients. The aims of the treatment of AVN are to maintain range of movement of the hip whilst preventing collapse of the femoral head. Clear treatment guidelines of this condition do not currently exist and the treatment of this condition can be difficult and unrewarding. Method: Dynamic arthrograms were used to assess of cases of AVN in order to determine the method of treatment. We present 20 sequential cases of AVN in patients presenting to our unit with SCFE and report the long-term results of treatment with a mean follow-up in excess of 10 years. Results: In 100 consecutive cases of SUFE there were 20 cases of AVN. There were 18 cases of salvage surgery and one patient refused surgery. Of the 18, there were 2 acetabuloplasty procedures, 12 proximal valgus osteotomies and 4 arthrodeses. At a later date there were 3 proximal femoral osteotomies and 5 total hip replacements. Discussion: There is a good functional result in the majority of cases and a logical approach delays the need of total hip replacement in the majority of cases. The management depends on the radiography, the arthogram and the EUA. If there is early AVN with no collapse the treatment is a shelf procedure. If there is hinge abduction the treatment is a valgus femoral osteotomy. If there is instable movement and the hip is not congruent the treatment is hip arthrodesis

Introduction: The management of a hip destroyed by infection during growth is difficult and controversial. Two clinical cases illustrate differing management options and question what might be the best solution for this problem. Case 1: A 12-year-old girl presented with a Staphylococcus aureus septic arthritis of the left hip. She underwent an arthrodesis of the hip one-year later because of a poor position of the hip. She had 20mm of shortening of the left lower limb. After 6 years of “normal” life she received a total hip replacement when aged 19 years. Since then she has no pain and has 12 mm of shortening of her left lower limb and a mobile left hip (100/0, 40/30, 30/30) and works as a cashier. Case 2 A 2-year-old boy presented with a Salmonella septicaemia and septic arthritis of the right hip. The hip deteriorated but the parents refused a hip arthrodesis. He underwent a Colonna procedure in 1994. Five years later he had developed 50mm of shortening in the right lower limb and he had an epiphysiodesis of the left knee. He is now 17 years old, has a painless hip, satisfactory range of movement (90/0, 0/15, 5/5), a slight limp, equal leg length and enjoys normal teenager activities. Radiographs suggest that he would benefit from a hip replacement

Introduction: Arthodesis provides a durable, painless and stable hip. Conversion to arthroplasty was has been recommended to relieve the excessive stresses in the neighbouring joints. We present the long term results following conversion of hip athrodesis to total hip artho-plasty at specialist hip centre. Method and material: 67 patients underwent the conversion between 1963 and 2000 at the centre for hip surgery, wrightington hospital were included in the study. 45 patients are available for the evaluation. Merle d’ Aubigne and Postel as modified by Charnley was used for clinical scoring. The most recent radiograph in patients with surviving arthoplasty was analysed. Results: The mean age at the time of arthodesis was 16.8 years. The conversion to hip arthroplasty was performed after a mean period of 32.3 years (range 12 to 54 years). The mean folowup was 16.37years (range 2–28). The mean Merle d’ Aubigne and Postel score increased from 7.95 to 13.45 postoperatively. All the patients were delighted with the conversion. 7 patients had revision and 1 had pseudoarthrosis. Conclusion: Hip arthrodesis is a useful holding procedure for young persons with painful hip. This could be successfully converted to Hip arthroplasty after an interval of relatively high physical activity during young adult life