The orientation of the acetabular component is influenced not only by the orientation at which the surgeon implants the component, but also the orientation of the pelvis at the time of implantation. Hence, the orientation of the pelvis at set-up and its movement during the operation, are important. During 67 hip replacements, using a validated photogrammetric technique, we measured how three surgeons orientated the patient’s pelvis, how much the pelvis moved during surgery, and what effect these had on the final orientation of the acetabular component. Pelvic orientation at set-up, varied widely (mean (± 2, standard deviation (sd))): tilt 8° (2sd ±32), obliquity –4° (2sd ±12), rotation –8° (2sd ±14). Significant differences in pelvic positioning were detected between surgeons (p < 0.001). The mean angular movement of the pelvis between set-up and component implantation was 9° (sd 6). Factors influencing pelvic movement included surgeon, approach (posterior >  lateral), procedure (hip resurfacing > total hip replacement) and type of support (p < 0.001). Although, on average, surgeons achieved their desired acetabular component orientation, there was considerable variability (2sd ±16) in component orientation. We conclude that inconsistency in positioning the patient at set-up and movement of the pelvis during the operation account for much of the variation in acetabular component orientation. Improved methods of positioning and holding the pelvis are required.

Cite this article: Bone Joint J 2014; 96-B:876–83.

Cubitus varus is the most frequent complication following the treatment of supracondylar humeral fractures in children. We investigated data from publications reporting on the surgical management of cubitus varus found in electronic searches of Ovid/MEDLINE and Cochrane Library databases. In 894 children from 40 included studies, the mean age at initial injury was 5.7 years (3 to 8.6) and 9.8 years (4 to 15.7) at the time of secondary correction. The four osteotomy techniques were classified as lateral closing wedge, dome, complex (multiplanar) and distraction osteogenesis. A mean angular correction of 27.6º (18.5° to 37.0°) was achieved across all classes of osteotomy. The meta-analytical summary estimate for overall rate of good to excellent results was 87.8% (95% CI 84.4 to 91.2). No technique was shown to significantly affect the surgical outcome, and the risk of complications across all osteotomy classes was 14.5% (95% CI 10.6 to 18.5). Nerve palsies occurred in 2.53% of cases (95% CI 1.4 to 3.6), although 78.4% were transient. No one technique was found to be statistically safer or more effective than any other.

Cite this article: Bone Joint J 2014;96-B:691–700.

The most widely used classification system for acetabular fractures was developed by Judet, Judet and Letournel over 50 years ago primarily to aid surgical planning. As population demographics and injury mechanisms have altered over time, the fracture patterns also appear to be changing. We conducted a retrospective review of the imaging of 100 patients with a mean age of 54.9 years (19 to 94) and a male to female ratio of 69:31 seen between 2010 and 2013 with acetabular fractures in order to determine whether the current spectrum of injury patterns can be reliably classified using the original system.

Three consultant pelvic and acetabular surgeons and one senior fellow analysed anonymous imaging. Inter-observer agreement for the classification of fractures that fitted into defined categories was substantial, (κ = 0.65, 95% confidence interval (CI) 0.51 to 0.76) with improvement to near perfect on inclusion of CT imaging (κ = 0.80, 95% CI 0.69 to 0.91). However, a high proportion of injuries (46%) were felt to be unclassifiable by more than one surgeon; there was moderate agreement on which these were (κ = 0.42 95% CI 0.31 to 0.54).

Further review of the unclassifiable fractures in this cohort of 100 patients showed that they tended to occur in an older population (mean age 59.1 years; 22 to 94 vs 47.2 years; 19 to 94; p = 0.003) and within this group, there was a recurring pattern of anterior column and quadrilateral plate involvement, with or without an incomplete posterior element injury.

Cite this article: Bone Joint J 2015;97-B:1139–43.

The August 2015 Hip & Pelvis Roundup360 looks at: The well-fixed acetabular revision; Predicting complications in revision arthroplasty; Is infection associated with fixation?; Front or back? An enduring question in hip surgery; Muscle-sparing approaches?; Gabapentin as a post-operative analgesic adjunct; An Indian take on AVN of the hip; Weight loss and arthroplasty

Periprosthetic femoral fracture (PFF) is a potentially devastating complication after total hip arthroplasty, with historically high rates of complication and failure because of the technical challenges of surgery, as well as the prevalence of advanced age and comorbidity in the patients at risk.

This study describes the short-term outcome after revision arthroplasty using a modular, titanium, tapered, conical stem for PFF in a series of 38 fractures in 37 patients.

The mean age of the cohort was 77 years (47 to 96). A total of 27 patients had an American Society of Anesthesiologists grade of at least 3. At a mean follow-up of 35 months (4 to 66) the mean Oxford Hip Score (OHS) was 35 (15 to 48) and comorbidity was significantly associated with a poorer OHS. All fractures united and no stem needed to be revised. Three hips in three patients required further surgery for infection, recurrent PFF and recurrent dislocation and three other patients required closed manipulation for a single dislocation. One stem subsided more than 5 mm but then stabilised and required no further intervention.

In this series, a modular, tapered, conical stem provided a versatile reconstruction solution with a low rate of complications.

Cite this article: Bone Joint J 2015;97-B:1031–7.

In this paper we propose a new classification of neurogenic peri-articular heterotopic ossification (HO) of the hip based on three-dimensional (3D) CT, with the aim of improving pre-operative planning for its excision.

A total of 55 patients (73 hips) with clinically significant HO after either traumatic brain or spinal cord injury were assessed by 3D-CT scanning, and the results compared with the intra-operative findings.

At operation, the gross pathological anatomy of the HO as identified by 3D-CT imaging was confirmed as affecting the peri-articular hip muscles to a greater or lesser extent. We identified seven patterns of involvement: four basic (anterior, medial, posterior and lateral) and three mixed (anteromedial, posterolateral and circumferential). Excellent intra- and inter-observer agreement, with kappa values > 0.8, confirmed the reproducibility of the classification system.

We describe the different surgical approaches used to excise the HO which were guided by the 3D-CT findings. Resection was always successful.

3D-CT imaging, complemented in some cases by angiography, allows the surgeon to define the 3D anatomy of the HO accurately and to plan its surgical excision with precision.

Cite this article: Bone Joint J 2015; 97-B:899–904.

Aims

The aim of this study was to identify risk factors for the failure of exchange nailing in nonunion of tibial diaphyseal fractures.

Tranexamic acid (TXA), an inhibitor of fibrinolysis, reduces blood loss after total knee arthroplasty. However, its effect on minimally invasive total hip arthroplasty (THA) is not clear. We performed a prospective, randomised double-blind study to evaluate the effect of two intravenous injections of TXA on blood loss in patients undergoing minimally invasive THA.

In total, 60 patients (35 women and 25 men with a mean age of 58.1 years; 17 to 84) who underwent unilateral minimally invasive uncemented THA were randomly divided into the study group (30 patients, 20 women and ten men with a mean age of 56.5 years; 17 to 79) that received two intravenous injections 1 g of TXA pre- and post-operatively (TXA group), and a placebo group (30 patients, 15 women and 15 men with a mean age of 59.5 years; 23 to 84). We compared the peri-operative blood loss of the two groups. Actual blood loss was calculated from the maximum reduction in the level of haemoglobin. All patients were followed clinically for the presence of venous thromboembolism.

The TXA group had a lower mean intra-operative blood loss of 441 ml (150 to 800) versus 615 ml (50 to 1580) in the placebo (p = 0.044), lower mean post-operative blood loss (285 ml (120 to 570) versus 392 ml (126 to 660) (p = 0.002), lower mean total blood loss (1070 ml (688 to 1478) versus 1337 ml (495 to 2238) (p = 0.004) and lower requirement for transfusion (p = 0.021). No patients in either group had symptoms of venous thromboembolism or wound complications.

This prospective, randomised controlled study showed that a regimen of two intravenous injections of 1 g TXA is effective for blood conservation after minimally invasive THA.

Cite this article: Bone Joint J 2015;97-B:905–10.

Oxidised zirconium (OxZi) has been developed as an alternative bearing surface for femoral heads in total hip arthroplasty (THA). This study has investigated polyethylene wear, functional outcomes and complications, comparing OxZi and cobalt–chrome (CoCr) as part of a three-arm, multicentre randomised controlled trial. Patients undergoing THA from four institutions were prospectively randomised into three groups. Group A received a CoCr femoral head and highly cross-linked polyethylene (XLPE) liner; Group B received an OxZi femoral head and XLPE liner; Group C received an OxZi femoral head and ultra-high molecular weight polyethylene (UHMWPE) liner. At five years, 368 patients had no statistically significant differences in short-form-36 (p = 0.176 mental, p = 0.756 physical), Western Ontario and McMaster Universities Osteoarthritis Index (p = 0.847), pain scores (p = 0.458) or complications. The mean rate of linear wear was 0.028 mm/year (standard deviation (sd) 0.010) for Group A, 0.023 mm/year (sd 0.010) for Group B, and 0.09 mm/year (sd 0.045) for Group C. Penetration was significantly higher in the UHMWPE liner group compared with both XLPE liner groups (p < 0.001) but no significant difference was noted between CoCr and OxZi when articulating with XLPE (p = 0.153). In this, the largest randomised study of this bearing surface, it appears that using a XLPE acetabular liner is more important in reducing THA component wear than the choice of femoral head bearing, at mid-term follow-up. There is a non-significant trend towards lower wear, coupling OxZi rather than CoCr with XLPE but long-term analysis is required to see if this observation changes with time and becomes significant.

Cite this article: Bone Joint J 2015;97-B:883–9.

The piriformis muscle is an important landmark in the surgical anatomy of the hip, particularly the posterior approach for total hip replacement (THR). Standard orthopaedic teaching dictates that the tendon must be cut in to allow adequate access to the superior part of the acetabulum and the femoral medullary canal. However, in our experience a routine THR can be performed through a posterior approach without sacrificing this tendon.

We dissected the proximal femora of 15 cadavers in order to clarify the morphological anatomy of the piriformis tendon. We confirmed that the tendon attaches on the crest of the greater trochanter, in a position superior to the trochanteric fossa, away from the entry point for broaching the intramedullary canal during THR. The tendon attachment site encompassed the summit and medial aspect of the greater trochanter as well as a variable attachment to the fibrous capsule of the hip joint. In addition we dissected seven cadavers resecting all posterior attachments except the piriformis muscle and tendon in order to study their relations to the hip joint, as the joint was flexed. At flexion of 90° the piriformis muscle lay directly posterior to the hip joint.

The piriform fossa is a term used by orthopaedic surgeons to refer the trochanteric fossa and normally has no relation to the attachment site of the piriformis tendon. In hip flexion the piriformis lies directly behind the hip joint and might reasonably be considered to contribute to the stability of the joint.

We conclude that the anatomy of the piriformis muscle is often inaccurately described in the current surgical literature and terms are used and interchanged inappropriately.

Cite this article: Bone Joint J 2013;95-B:764–9.

The purpose of this study was to evaluate the long-term outcome of patients with a sacral chordoma and the surgical management of locally recurrent disease.

Between October 1990 and August 2013 we operated on 54 consecutive patients with a sacral chordoma. There were 34 men and 20 women with a mean age of 60 years (25 to 86). The mean maximum diameter of the tumour was 9.3 cm (3 to 20).

The mean follow-up was 7.8 years (2 months to 23.4 years). The disease-specific survival was 82% at five years, 57% at ten years and 45% at 15 years. The local recurrence-free survival was 49% at five years, 37% at ten years and 20% at 15 years. Local recurrence occurred in 30 patients (56%) at a mean of 3.8 years (3 months to 13 years) post-operatively.

Survival after the treatment of recurrence was 89% at two years, 56% at five years and 19% at ten years. Of nine patients who had complete resection of a recurrence, one died after 72 months and eight remain disease-free. Incomplete resection of recurrent disease resulted in a survival of 54% at two years and 36% at five years.

For 12 patients with a local recurrence who were treated palliatively, survival was 81% at two years and 31% at five years.

A wide margin of resection gave the best chance of long-term survival and complete resection of local recurrence the best chance of control of disease.

Cite this article: Bone Joint J 2015;97-B:711–15.

The aim of this study was to investigate the relationship between the geometry of the proximal femur and the incidence of intra-operative fracture during uncemented total hip arthroplasty (THA).

We studied the pre-operative CT scans of 100 patients undergoing THA with an uncemented femoral component. We measured the anteroposterior and mediolateral dimensions at the level of division of the femoral neck to calculate the aspect ratio of the femur. Wide variations in the shape of the femur were observed, from round, to very narrow elliptic. The femurs of women were narrower than those of men (p < 0.0001) and small femurs were also narrower than large ones. Patients with an intra-operative fracture of the calcar had smaller and narrower femurs than those without a fracture (p < 0.05) and the implanted Corail stems were smaller in those with a fracture (mean size 9 vs 12, p < 0.0001).

The variability of the shape of the femoral neck at the level of division contributes to the understanding of the causation of intra-operative fractures in uncemented THA.

Cite this article: Bone Joint J 2015;97-B:741–8.

The aim of this study was to evaluate the ten-year clinical and functional outcome of hip resurfacing and to compare it with that of cementless hip arthroplasty in patients under the age of 55 years.

Between 1999 and 2002, 80 patients were enrolled into the study: 24 were randomised (11 to hip resurfacing, 13 to total hip arthroplasty), 18 refused hip resurfacing and chose cementless total hip arthroplasty with a 32 mm bearing, and 38 insisted on resurfacing. The mean follow-up for all patients was 12.1 years (10 to 14).

Patients were assessed clinically and radiologically at one year, five years and ten years. Outcome measures included EuroQol EQ5D, Oxford, Harris hip, University of California Los Angeles and University College Hospital functional scores.

No differences were seen between the two groups in the Oxford or Harris hip scores or in the quality of life scores. Despite a similar aspiration to activity pre-operatively, a higher proportion of patients with a hip resurfacing were running and involved in sport and heavy manual labour after ten years.

We found significantly higher function scores in patients who had undergone hip resurfacing than in those with a cementless hip arthroplasty at ten years. This suggests a functional advantage for hip resurfacing. There were no other attendant problems.

Cite this article: Bone Joint J 2015; 97-B:617–22.

Objectives

To study the vascularity and bone metabolism of the femoral head/neck following hip resurfacing arthroplasty, and to use these results to compare the posterior and the trochanteric-flip approaches.

Concerns have been raised that deformation of acetabular shells may disrupt the assembly process of modular prostheses. In this study we aimed to examine the effect that the strength of bone has on the amount of deformation of the acetabular shell. The hypothesis was that stronger bone would result in greater deformation. A total of 17 acetabular shells were inserted into the acetabula of eight cadavers, and deformation was measured using an optical measuring system. Cores of bone from the femoral head were taken from each cadaver and compressed using a materials testing machine. The highest peak modulus and yield stress for each cadaver were used to represent the strength of the bone and compared with the values for the deformation and the surgeon’s subjective assessment of the hardness of the bone. The mean deformation of the shell was 129 µm (3 to 340). No correlation was found between deformation and either the maximum peak modulus (r² = 0.011, t = 0.426, p = 0.676) or the yield stress (r² = 0.024, t = 0.614, p = 0.549) of the bone. Although no correlation was found between the strength of the bone and deformation, the values for the deformation observed could be sufficient to disrupt the assembly process of modular acetabular components.

Cite this article: Bone Joint J 2015; 97-B:473–7.

Aims

The aims of this study were to evaluate the clinical and radiological outcomes of instrumented posterolateral fusion (PLF) performed in patients with rheumatoid arthritis (RA).

We retrospectively reviewed the outcomes of 33 consecutive patients who had undergone an extra-articular, total or partial scapulectomy for a malignant tumour of the shoulder girdle between 1 July 2001 and 30 September 2013. Of these, 26 had tumours which originated in the scapula or the adjacent soft tissue and underwent a classic Tikhoff–Linberg procedure, while seven with tumours arising from the proximal humerus were treated with a modified Tikhoff-Linberg operation. We used a Ligament Advanced Reinforcement System for soft-tissue reconstruction in nine patients, but not in the other 24.

The mean Musculoskeletal Tumor Society score (MSTS) was 17.6 (95% confidence interval (CI) 15.9 to 19.4); 17.6 (95% CI 15.5 to 19.6) after the classic Tikhoff–Linberg procedure and 18.1 (95% CI 13.8 to 22.3) after the modified Tikhoff–Linberg procedure. Patients who had undergone a LARS soft-tissue reconstruction had a mean score of 18.6 (95% (CI) 13.9 to 22.4) compared with 17.2 (95% CI 15.5 to 19.0) for those who did not.

The Tikhoff–Linberg procedure is a useful method for wide resection of a malignant tumour of the shoulder girdle which helps to preserve hand and elbow function. The method of soft-tissue reconstruction has no effect on functional outcome.

Cite this article: Bone Joint J 2014;96-B:684–90.

Ceramic-on-metal (CoM) is a relatively new bearing combination for total hip arthroplasty (THA) with few reported outcomes. A total of 287 CoM THAs were carried out in 271 patients (mean age 55.6 years (20 to 77), 150 THAs in female patients, 137 in male) under the care of a single surgeon between October 2007 and October 2009. With the issues surrounding metal-on-metal bearings the decision was taken to review these patients between March and November 2011, at a mean follow-up of 34 months (23 to 45) and to record pain, outcome scores, radiological analysis and blood ion levels. The mean Oxford Hip Score was 19.2 (12 to 53), 254 patients with 268 hips (95%) had mild/very mild/no pain, the mean angle of inclination of the acetabular component was 44.8^o (28^o to 63^o), 82 stems (29%) had evidence of radiolucent lines of > 1 mm in at least one Gruen zone and the median levels of cobalt and chromium ions in the blood were 0.83 μg/L (0.24 μg/L to 27.56 μg/L) and 0.78 μg/L (0.21 μg/L to 8.84 μg/L), respectively. The five-year survival rate is 96.9% (95% confidence interval 94.7% to 99%).

Due to the presence of radiolucent lines and the higher than expected levels of metal ions in the blood, we would not recommend the use of CoM THA without further long-term follow-up. We plan to monitor all these patients regularly.

Cite this article: Bone Joint J 2015;97-B:300–5.

The orientation of the acetabular component can influence both the short- and long-term outcomes of total hip replacement (THR). We performed a prospective, randomised, controlled trial of two groups, comprising of 40 patients each, in order to compare freehand introduction of the component with introduction using the transverse acetabular ligament (TAL) as a reference for anteversion. Anteversion and inclination were measured on pelvic radiographs.

With respect to anteversion, in the freehand group 22.5% of the components were outside the safe zone versus 0% in the transverse acetabular ligament group (p = 0.002). The mean angle of anteversion in the freehand group was 21° (2° to 35°) which was significantly higher compared with 17° (2° to 25°) in the TAL group (p = 0.004). There was a significant difference comparing the variations of both groups (p = 0.008).

With respect to inclination, in the freehand group 37.5% of the components were outside the safe zone versus 20% in the TAL group (p = 0.14). There was no significant difference regarding the accuracy or variation of the angle of inclination when comparing the two groups.

The transverse acetabular ligament may be used to obtain the appropriate anteversion when introducing the acetabular component during THR, but not acetabular component inclination.

Cite this article: Bone Joint J 2014;96-B:312–18.

We have investigated iatrogenic popliteal artery injuries (PAI) during non arthroplasty knee surgery regarding mechanism of injury, treatment and outcomes, and to identify successful strategies when injury occurs.

In all, 21 iatrogenic popliteal artery injuries in 21 patients during knee surgery other than knee arthroplasty were identified from the Swedish Vascular Registry (Swedvasc) between 1987 and 2011. Prospective registry data were supplemented with case-records, including long-term follow-up. In total, 13 patients suffered PAI during elective surgery and eight during urgent surgery such as fracture fixation or tumour resection. Nine injuries were detected intra-operatively, five within 12 to 48 hours and seven > 48 hours post-operatively (two days to 23 years).

There were 19 open vascular and two endovascular surgical repairs. Two patients died within six months of surgery. One patient required amputation. Only six patients had a complete recovery of whom had the vascular injury detected at time of injury and repaired by a vascular surgeon. Patients sustaining vascular injury during elective procedures are more likely to litigate (p = 0.029).

We conclude that outcomes are poorer when there is a delay of diagnosis and treatment, and that orthopaedic surgeons should develop strategies to detect PAI early and ensure rapid access to vascular surgical support.

Cite this article: Bone Joint J 2015;97-B:192–6.