The 3-dot circle: A reliable method for safe and efficient digital templating of the acetabular component.

BACKGROUND: Templating for preoperative planning of joint arthroplasty has followed the evolution of digital templating software. OBJECTIVE: This study aims to provide a safe, reliable and reproducible method for prediction of acetabular component size based on measurement of the radiographic femoral head diameter, with the aid of templating software. METHODS: A defined methodology for femoral head measurement was applied to 97 consecutive, calibrated digital pelvic radiographs. Based on radiographic femoral head diameter, the minimum acetabular shell diameter was calculated and then compared to the size of the implanted acetabular shells. RESULTS: This method predicted safe minimum acetabular component size with an accuracy of 95.9% with a high inter-observer reliability of 97.6%. CONCLUSIONS: This study presents a simple, reproducible and accurate method for templating of the minimum safest acetabular component diameter.

A Dual Biomechanical Failure: Exeter Stem and Pubic Rami Insufficiency Fracture, following Hybrid Total Hip Arthroplasty.

Introduction. Incidence of Exeter stem fracture is extremely uncommon. Pubic rami insufficiency fractures following arthroplasty are also rare. To our knowledge no cases of spontaneous stem failure with previous insufficiency fractures have yet been reported. Case Presentation. This report describes a case of spontaneous fracture through a cemented Exeter stem in a 66-year-old patient who had previously undergone a hybrid total hip replacement and was found to have bifocal pubic rami insufficiency fractures. The patient presented 18-year postprimary surgery with spontaneous fracture of the middle third of the cemented femoral stem and adjacent proximal femur. Conclusion. This report demonstrates a unique case of Exeter stem fracture with previous pelvic insufficiency fractures. The case adds to the rare occurrences of Exeter stem failure in the literature and highlights the risk of potential insufficiency fractures in patients undergoing total hip replacement.

Do professional athletes perform better than recreational athletes after arthroscopy for femoroacetabular impingement?

BACKGROUND: Although a large number of athletes' returns to sports after hip arthroscopic surgery for femoroacetabular impingement (FAI), it is not clear if they do so to the preinjury level and whether professional athletes (PA) are more likely to return to the preinjury level compared with recreational athletes (RA). QUESTIONS/PURPOSES: We therefore compared (1) the time taken to return to the preinjury level of sport between professional and recreational athletes; (2) the degree of improvement in time spent in training and competitive activities after arthroscopic surgery for FAI; and (3) the difference in trend of improvement in hip scores. METHODS: We prospectively followed 80 athletes (PA = 40, RA = 40; mean age, 35.7 years; males = 50, females = 30; mean followup, 1.4 years; range, 1-1.8 years) who underwent hip arthroscopy for FAI. We measured the time to return to sports; training time and time in competition; and the modified Harris hip score and the nonarthritic hip score. RESULTS: There was a 2.6-fold improvement in the training time (from 7.8 to 20 hours per week) and a 3.2-fold increase in time in competition (from 2.5 to 7.9 hours per week) 1 year after surgery. The mean time to return to sporting activities was 5.4 months, which was lower for PA (4.2) as compared with RA (6.8). Eighty-two percent (66) (PA = 88% [35] versus RA = 73% [29]) returned to their preinjury level of sport within 1 year of surgery. CONCLUSIONS: The data suggest PA may show quicker return to sports than RA but the hip scores and rate of return to sports are similar.

The prevalence of dysplasia in femoroacetabular impingement.

It is unknown how often femoro-acetabular impingement (FAI) and hip dysplasia co-exist and which is more important in the development of intra-articular lesions such as labral tears. This study identified the prevalence of dysplasia on standard radiographs in a group of 76 consecutive patients with symptomatic FAI. The centre-edge (CE) angle of Wiberg, the acetabular angle (AA) of Sharp, FAI type, offset ratio and posterior wall sign were identified. 63 patients, predominantly young adult males (mean age: 34.6 years; 10:4 male-to-female ratio), met our inclusion criteria. Most females (13:18) showed signs of dysplasia based on the AA. No association of dysplasia with FAI group, offset ratio or posterior wall sign was found. 47% of our patients with FAI also had radiographic evidence of dysplasia (3-15% definite and 9-30% borderline, depending on the angle utilised). Surgery for FAI should therefore take into account the presence of co-existing dysplasia. Conversely, surgery for dysplasia should take into consideration the co-existence of FAI. The prime cause of labral pathology in the presence of dysplasia may be co-existent FAI and the latter problem may demand priority, not the former.

Intrinsic passive stiffness of 2 constructs of varus proximal femoral osteotomy: external fixator or blade plate.

BACKGROUND: Despite the published clinical evidence of the implementation of external fixation of proximal femoral osteotomies, there is lack of specific laboratory justification. METHODS: Two groups of 5 adult composite femur constructs of varus proximal femoral osteotomy were tested under incremental and cyclical loading of up to 600N along the mechanical axis. Five were fixed with a blade plate and another 5 with a monolateral external fixator. Load versus displacement curves were produced, and passive stiffness of all constructs was calculated. The described loading regime aimed to simulate the initial postoperative state and provide data for the assessment of vertical intrinsic passive stiffness in partial weight-bearing conditions. RESULTS: Although the blade plate constructs showed higher average stiffness, this was not statistically significant [F(1,8)=1.712, P=0.23]. No construct failed. No failure or plastic deformation was observed under the described loading regime. CONCLUSIONS: Vertical intrinsic passive stiffness in partial weight-bearing conditions during the initial postoperative period can be considered satisfactory subsequent to unilateral external fixation of a varus intertrochanteric osteotomy. CLINICAL RELEVANCE: The results support the hypothesis that external fixation is a biomechanically sound alternative to internal fixation of varus intertrochanteric osteotomies, in selected patients.

Prevalence of chest trauma, associated injuries and mortality: a level I trauma centre experience.

A review of prospectively collected data in our trauma unit for the years 1998-2003 was undertaken. Adult patients who suffered multiple trauma with an Injury Severity Score (ISS) of >/=16, admitted to hospital for more than 72 hours and with sustained blunt chest injuries were included in the study. Demographic details including pre-hospital care, trauma history, admission vital signs, blood transfusions, details of injuries and their abbreviated injury scores (AIS), operations, length of intensive care unit and hospital stays, Injury Severity Score (ISS) and mortality were analysed. Fulfilling the inclusion criteria with at least one chest injury were 1,164 patients. The overall mortality reached 18.7%. As expected, patients in the higher AIS groups had both a higher overall ISS and mortality rate with one significant exception; patients with minor chest injuries (AIS(chest) = 1) were associated with mortality comparable to injuries involving an AIS(chest) = 3. Additionally, the vast majority of polytraumatised patients with an AIS(chest) = 1 died in ICU sooner than patients of groups 2-5.

Biological enhancement of tibial diaphyseal aseptic non-unions: the efficacy of autologous bone grafting, BMPs and reaming by-products.

The mandatory stimulus that can optimise the healing pathway can be electrical, mechanical, biological, or a combination of all these parameters. A variety of means has been utilised for biological enhancement, including extracorporeal shock wave, electrical, ultrasound stimulation, the reaming technique of IM nailing, bone graft substitutes, osteogenic cells and bioactive molecules produced by tissue engineering techniques. The aim of this study is to present a review of the existing evidence for the efficacy of reaming, autologous bone grafting and the commercially available growth factors (BMP-2 and BMP-7) for the treatment of aseptic tibial non-unions. The gold standard method of enhancing bone healing in cases of tibial non-union remains the autologous bone graft. Autogenous bone grafts possess osteoconductive, osteoinductive properties and also osteoprogenitor cells. However, their harvesting is associated with high morbidity and many complications reaching percentages of 30%. Intramedullary reamed nailing, either used as an alternative fixation method or as an exchange to a wider implant, offers the unique biomechanical advantages of an intramedullary device, together with the osteoinductive stimulus of the by-products of reaming, and the aptitude for early weight-bearing and active rehabilitation. The safety of administration of the commercial distributed growth factors (BMP-2 and BMP-7), combined with the lack of the morbidity and the quantity restrictions that characterise autologous bone grafts, have given to this family of molecules a principal role between the other bone graft substitutes. On average the union rates reported in the 20 manuscripts that have been evaluated range from 58.3% to 100%, and the average time to union from 12.5 weeks to 48.4 weeks, indicating the significant discrepancies in the reported evidence and the multiplicity of different treatment strategies.