Introduction. Bernese periacetabular osteotomy (PAO) repositions the acetabulum to increase femoral head coverage (FHC) in hip dysplasia. Currently, there is a paucity of objective peri-operative metrics to plan for optimal acetabular fragment repositioning. The MSk Lab Hip 3D Planner (MSkL-HP) measures acetabular morphology and simulates PAO cuts to achieve optimal FHC. We evaluated how adjusting location and orientation of cutting planes can alter FHC. Method. MSkL-HP simulated 274 feasible PAOs on four dysplastic hips. Femoroacetabular anatomy was landmarked to simulate cutting planes. Posterior column and ischial cuts were standardised, whilst iliac and pubic cut combinations varied. The slope of the iliac cut was either neutral (aligned to pelvis), exit point 5mm above the entry point (+5), or 5mm below (-5). The slope of the pubic cut was either 90°, 50°, or 70° (medial-to-lateral). Iliac and pubic cuts were simulated 0, 5 and 15mm - distal and medial – to a classic cut. Outcome measures were achieved LCEA, Tönnis, FHC and % bone overlap at the pubic cut. Targets were LCEA >30°, Tönnis angle <10°, and FHC >70% and minimum bone overlap ≥10%. Results. All feasible PAOs resulted in improvement from pre-operative metrics. Personalised cutting planes provided greater benefit than standard planes. Kruskal Wallis tests showed that the iliac cut at 5mm or 15mm resulted in a greater LCEA and lower Tönnis compared to the classic cut (p<0.05). Changing location of the pubic cut, and slope of the iliac and pubic cuts did not significantly affect LCEA and Tönnis in all hips (p<0.05). Cut combinations optimising metrics were associated with a lower % pubic cut overlap. Conclusion. MSkL-HP feasibly and reliably planned personalised PAO, measuring pre-operative and simulated post-operative objective metrics. Patient-specific pubic and iliac cuts enable greater correction whilst maintaining bone overlap. Further simulations on patients with varying morphology may improve standard techniques

Complex spinal deformities can cause pain, neurological symptoms and imbalance (sagittal and/or coronal), severely impairing patients’ quality of life and causing disability. Their treatment has always represented a tough challenge: prior to the introduction of modern internal fixation systems, the only option was an arthrodesis to prevent worsening of the deformity. Then, the introduction of pedicle screws allowed the surgeons to perform powerful corrective manoeuvres, distributing forces over multiple levels, to which eventually associate osteotomies. In treating flexible coronal deformities, in-ternal fixation and corrective manoeuvres may be sufficient: the combination of high density pedicle screws and direct vertebral rotation revolutionized surgical treatment of scoliosis. However, spinal osteotomies are needed for correcting complex rigid deformities; the type of osteot-omy must be chosen according to the aetiology, type and apex of the deformity. When dealing with large radius deformities, spread over multiple levels and without fusion, multiple posterior column os-teotomies such as Smith-Petersen and Ponte (asymmetric, when treating scoliosis) can be performed, dissipating the correction over many levels. Conversely, the management of a sharp, angulated de-formity that involves a few vertebral levels and/or with bony fusion, requires more aggressive 3 col-umn osteotomies such as Pedicle Subtraction Osteotomies (PSO), Bone Disc Bone Osteotomies (BDBO) or Vertebral Column Resection (VCR). Sometimes the deformity is so severe that cannot be corrected with only one osteotomy: in this scenario, multilevel osteotomies can be performed

Introduction. Acetabular fractures are a challenging problem. It has been published that outcome is dependent upon the type of fracture, the reduction of the fracture and concomitant injuries. The end-points of poor outcome include avascular necrosis of the femoral head, osteoarthritis. However, we lack definitive statistics and so counselling patients on prognosis could be improved. In order to achieve this, more outcome studies from tertiary referral centres are required. We present the first long term follow up from a large tertiary referral centre in Ireland. Methods. We identified all patients who were ten years following open reduction and internal fixation of an acetbular fracture in our centre. We invited all of these patients to attend the hospital for clinical and radiographic follow-up. As part of this, three scoring systems were completed for each patient; the Short-form 36 health survey (SF36), the Merle d'Aubigné score and the Short Musculoskeletal Functional Assessment (SMFA). Results. The data represents one year's activity at a new tertiary referral unit. We identified a total of 44 patients who were ten years following ORIF of acetabular fractures in our unit. 21 patients (48%) replied to written invitation and attended the hospital for clinical and radiographic follow-up. A further 7 patients were contacted by telephone and interviewed to gauge their rehabilitation. 3 patients had passed away. The remaining 13 patients were not contactable. Of those who attended in person for follow-up; 18 were male and 3 were female. The mean age at follow-up was 40.5 years (Range 27-60). In terms of fracture pattern epidemiology, 43% of patients sustained posterior column and wall fractures, 29% posterior wall, 14% posterior column alone, 9.5% transverse with posterior wall and 9.5% bicolumnar. 2 patients in the follow-up group had total hip replacements. Of the remaining patients the overall mean SF36 score was 78.8% (SD 16.4). The mean SMFA was 14.1% (SD 5). The mean Merle d'Aubigné score was 14.9 (SD 3.2) with 63% graded as good or excellent. Comparison of outcome between sub-groups according to fracture classification showed no significant difference. Traumatic sciatic nerve injury was sustained by four patients in the follow-up group and all patients continued to complain of ongoing weakness. Of the patients who were contacted via telephone, 2 had total hip replacements. The remaining 5 reported no significant problems with their hips and cited this as the reason for not attending follow-up. Conclusion. Overall the outcome of the patients was more favourable than expected. This was supported by the results of the clinical scoring systems. In some patients this also appeared to be despite poor radiographic findings. Our observations suggest that concomitant injuries, especially sciatic nerve injury have a profound negative influence on the patients' ability to fully rehabilitate. These data provide a valuable tool for the trauma surgeon in providing the patient with an educated prognosis

3D imaging is commonly employed in the surgical planning and management of bony deformity. The advent of desktop 3D printing now allows rapid in-house production of specific anatomical models to facilitate surgical planning. The aim of this pilot study was to evaluate the feasibility of creating 3D printed models in a university hospital setting. For requested cases of interest, CT DICOM images on the local NHS Picture Archive System were anonymised and transferred. Images were then segmented into 3D models of the bones, cleaned to remove artefacts, and orientated for printing with preservation of the regions of interest. The models were printed in polylactic acid (PLA), a biodegradable thermoplastic, on the CubeX Duo 3D printer. PLA models were produced for 4 clinical cases; a complex forearm deformity as a result of malunited childhood fracture, a pelvic discontinuity with severe acetabular deficiency following explantation of an infected total hip replacement, a chronically dislocated radial head causing complex elbow deformity as a result of a severe skeletal dysplasia, and a preoperative model of a deficient proximal tibia as a result of a severe tibia fracture. The models materially influenced clinical decision making, surgical intervention planning and required equipment. In the case of forearm an articulating model was constructed allowing the site of impingement between radius and ulnar to be identified, an osteotomy was practiced on multiple models allowing elimination of the block to supination. This has not previously been described in literature. The acetabulum model allowed pre-contouring of a posterior column plate which was then sterilised and eliminated a time consuming intraoperative step. While once specialist and expensive, in house 3D printing is now economically viable and a helpful tool in the management of complex patients

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