Objectives

The purpose of this study was to develop an accurate, reliable and easily applicable method for determining the anatomical location of the joint line during revision knee arthroplasty.

Patients from a randomised trial on resurfacing hip arthroplasty (RHA) (n = 36, 19 males; median age 57 years, 24 to 65) comparing a conventional 28 mm metal-on-metal total hip arthroplasty (MoM THA) (n = 28, 17 males; median age 59 years, 37 to 65) and a matched control group of asymptomatic patients with a 32 mm ceramic-on-polyethylene (CoP) THA (n = 33, 18 males; median age 63 years, 38 to 71) were cross-sectionally screened with metal artefact reducing sequence-MRI (MARS-MRI) for pseudotumour formation at a median of 55 months (23 to 72) post-operatively. MRIs were scored by consensus according to three different classification systems for pseudotumour formation.

Clinical scores were available for all patients and metal ion levels for MoM bearing patients.

Periprosthetic lesions with a median volume of 16 mL (1.5 to 35.9) were diagnosed in six patients in the RHA group (17%), one in the MoM THA group (4%) and six in the CoP group (18%). The classification systems revealed no clear differences between the groups. Solid lesions (n = 3) were exclusively encountered in the RHA group. Two patients in the RHA group and one in the MoM THA group underwent a revision for pseudotumour formation. There was no statistically significant relationship between clinical scoring, metal ion levels and periprosthetic lesions in any of the groups.

Periprosthetic fluid collections are seen on MARS-MRI after conventional CoP THA and RHA and may reflect a soft-tissue collection or effusion.

Currently available MRI classification systems seem to score these collections as pseudotumours, causing an-overestimatation of the incidence of pseudotumours.

Cite this article: Bone Joint J 2015;97-B:1175–82.

Aims

The aim of this study is to introduce and investigate the efficacy and feasibility of a new vertebral osteotomy technique, vertebral column decancellation (VCD), for rigid thoracolumbar kyphotic deformity (TLKD) secondary to ankylosing spondylitis (AS).

Aims

The aim of this study was a quantitative analysis of a surgeon’s learning curve for scoliosis surgery and the relationship between the surgeon’s experience and post-operative outcomes, which has not been previously well described.

Cancellous allograft bone chips are commonly used in the reconstruction of defects in bone after removal of benign tumours. We investigated the MRI features of grafted bone chips and their change over time, and compared them with those with recurrent tumour. We retrospectively reviewed 66 post-operative MRIs from 34 patients who had undergone curettage and grafting with cancellous bone chips to fill the defect after excision of a tumour. All grafts showed consistent features at least six months after grafting: homogeneous intermediate or low signal intensities with or without scattered hyperintense foci (speckled hyperintensities) on T1 images; high signal intensities with scattered hypointense foci (speckled hypointensities) on T2 images, and peripheral rim enhancement with or without central heterogeneous enhancements on enhanced images. Incorporation of the graft occurred from the periphery to the centre, and was completed within three years. Recurrent lesions consistently showed the same signal intensities as those of pre-operative MRIs of the primary lesions. There were four misdiagnoses, three of which were chondroid tumours.

We identified typical MRI features and clarified the incorporation process of grafted cancellous allograft bone chips. The most important characteristics of recurrent tumours were that they showed the same signal intensities as the primary tumours. It might sometimes be difficult to differentiate grafted cancellous allograft bone chips from a recurrent chondroid tumour.

Cite this article: Bone Joint J 2015;97-B:121–8.

Aims

The aim of this study was to examine the results of revision total knee arthroplasty (TKA) undertaken for stiffness in the absence of sepsis or loosening.

The pre-operative differentiation between enchondroma, low-grade chondrosarcoma and high-grade chondrosarcoma remains a diagnostic challenge. We reviewed the accuracy and safety of the radiological grading of cartilaginous tumours through the assessment of, first, pre-operative radiological and post-operative histological agreement, and second the rate of recurrence in lesions confirmed as high-grade on histology. We performed a retrospective review of major long bone cartilaginous tumours managed by curettage as low grade between 2001 and 2012. A total of 53 patients with a mean age of 47.6 years (8 to 71) were included. There were 23 men and 30 women. The tumours involved the femur (n = 20), humerus (n = 18), tibia (n = 9), fibula (n = 3), radius (n = 2) and ulna (n = 1). Pre-operative diagnoses resulted from multidisciplinary consensus following radiological review alone for 35 tumours, or with the addition of pre-operative image guided needle biopsy for 18. The histologically confirmed diagnosis was enchondroma for two (3.7%), low-grade chondrosarcoma for 49 (92.6%) and high-grade chondrosarcoma for two (3.7%). Three patients with a low-grade tumour developed a local recurrence at a mean of 15 months (12 to 17) post-operatively. A single high-grade recurrence (grade II) was treated with tibial diaphyseal replacement. The overall recurrence rate was 7.5% at a mean follow-up of 4.7 years (1.2 to 12.3). Cartilaginous tumours identified as low-grade on pre-operative imaging with or without additional image-guided needle biopsy can safely be managed as low-grade without pre-operative histological diagnosis. A few tumours may demonstrate high-grade features histologically, but the rates of recurrence are not affected.

Cite this article: Bone Joint J 2014; 96-B:1098–105.

We evaluated the accuracy with which a custom-made acetabular component could be positioned at revision arthroplasty of the hip in patients with a Paprosky type 3 acetabular defect.

A total of 16 patients with a Paprosky type 3 defect underwent revision surgery using a custom-made trabecular titanium implant. There were four men and 12 women with a median age of 67 years (48 to 79). The planned inclination (INCL), anteversion (AV), rotation and centre of rotation (COR) of the implant were compared with the post-operative position using CT scans.

A total of seven implants were malpositioned in one or more parameters: one with respect to INCL, three with respect to AV, four with respect to rotation and five with respect to the COR.

To the best of our knowledge, this is the first study in which CT data acquired for the pre-operative planning of a custom-made revision acetabular implant have been compared with CT data on the post-operative position. The results are encouraging.

Cite this article: Bone Joint J 2015; 97-B:780–5.

We performed a CT-based computer simulation study to determine how the relationship between any inbuilt posterior slope in the proximal tibial osteotomy and cutting jig rotational orientation errors affect tibial component alignment in total knee replacement. Four different posterior slopes (3°, 5°, 7° and 10°), each with a rotational error of 5°, 10°, 15°, 20°, 25° or 30°, were simulated. Tibial cutting block malalignment of 20° of external rotation can produce varus malalignment of 2.4° and 3.5° with a 7° and a 10° sloped cutting jig, respectively. Care must be taken in orientating the cutting jig in the sagittal plane when making a posterior sloped proximal tibial osteotomy in total knee replacement.

Cite this article: Bone Joint J 2013;95-B:1201–3.

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.

Aims

The objective of this double-blind randomised controlled trial was to assess whether ultrasound guidance improved the efficacy of corticosteroid injections for Morton’s neuroma (MN).

We performed a retrospective review of a consecutive series of 178 Mobility total ankle replacements (TARs) performed by three surgeons between January 2004 and June 2009, and analysed radiological parameters and clinical outcomes in a subgroup of 129 patients. The mean follow-up was 4 years (2 to 6.3). A total of ten revision procedures (5.6%) were undertaken. The mean Ankle Osteoarthritis Scale (AOS) pain score was 17 (0 to 88) and 86% of patients were clinically improved at follow-up. However, 18 patients (18 TARs, 14%) had a poor outcome with an AOS pain score of > 30. A worse outcome was associated with a pre-operative diagnosis of post-traumatic degenerative arthritis. However, no pre- or post-operative radiological parameters were significantly associated with a poor outcome. Of the patients with persistent pain, eight had predominantly medial-sided pain. Thirty TARs (29%) had a radiolucency in at least one zone.

The outcome of the Mobility TAR at a mean of four years is satisfactory in > 85% of patients. However, there is a significant incidence of persistent pain, particularly on the medial side, for which we were unable to establish a cause.

Cite this article: Bone Joint J 2013;95-B:1366–71.

In arthritis of the varus knee, a high tibial osteotomy (HTO) redistributes load from the diseased medial compartment to the unaffected lateral compartment.

We report the outcome of 36 patients (33 men and three women) with 42 varus, arthritic knees who underwent HTO and dynamic correction using a Garches external fixator until they felt that normal alignment had been restored. The mean age of the patients was 54.11 years (34 to 68). Normal alignment was achieved at a mean 5.5 weeks (3 to 10) post-operatively. Radiographs, gait analysis and visual analogue scores for pain were measured pre- and post-operatively, at one year and at medium-term follow-up (mean six years; 2 to 10). Failure was defined as conversion to knee arthroplasty.

Pre-operative gait analysis divided the 42 knees into two equal groups with high (17 patients) or low (19 patients) adductor moments. After correction, a statistically significant (p < 0.001, t-test,) change in adductor moment was achieved and maintained in both groups, with a rate of failure of three knees (7.1%), and 89% (95% confidence interval (CI) 84.9 to 94.7) survivorship at medium-term follow-up.

At final follow-up, after a mean of 15.9 years (12 to 20), there was a survivorship of 59% (95% CI 59.6 to 68.9) irrespective of adductor moment group, with a mean time to conversion to knee arthroplasty of 9.5 years (3 to 18; 95% confidence interval ± 2.5).

HTO remains a useful option in the medium-term for the treatment of medial compartment osteoarthritis of the knee but does not last in the long-term.

Cite this article: Bone Joint J 2016;98-B:601–7.

The February 2014 Foot & Ankle Roundup³⁶⁰ looks at: optimal medial malleolar fixation; resurfacing in the talus; predicting outcome in mobility ankles; whether mal-aligned ankles can be successfully replaced; cartilage colonisation in bipolar ankle grafts; CTs and proof of fusion; recalcitrant Achilles tendinopathy; and recurrent fifth metatarsal stress fractures.

We have previously reported the short-term radiological results of a randomised controlled trial comparing kinematically aligned total knee replacement (TKR) and mechanically aligned TKR, along with early pain and function scores. In this study we report the two-year clinical results from this trial. A total of 88 patients (88 knees) were randomly allocated to undergo either kinematically aligned TKR using patient-specific guides, or mechanically aligned TKR using conventional instruments. They were analysed on an intention-to-treat basis. The patients and the clinical evaluator were blinded to the method of alignment.

At a minimum of two years, all outcomes were better for the kinematically aligned group, as determined by the mean Oxford knee score (40 (15 to 48) versus 33 (13 to 48); p = 0.005), the mean Western Ontario McMaster Universities Arthritis index (WOMAC) (15 (0 to 63) versus 26 (0 to 73); p = 0.005), mean combined Knee Society score (160 (93 to 200) versus 137 (64 to 200); p= 0.005) and mean flexion of 121° (100 to 150) versus 113° (80 to 130) (p = 0.002). The odds ratio of having a pain-free knee at two years with the kinematically aligned technique (Oxford and WOMAC pain scores) was 3.2 (p = 0.020) and 4.9 (p = 0.001), respectively, compared with the mechanically aligned technique. Patients in the kinematically aligned group walked a mean of 50 feet further in hospital prior to discharge compared with the mechanically aligned group (p = 0.044).

In this study, the use of a kinematic alignment technique performed with patient-specific guides provided better pain relief and restored better function and range of movement than the mechanical alignment technique performed with conventional instruments.

Cite this article: Bone Joint J 2014;96-B:907–13.

Aims

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

Aims

Glenoid bone loss can be a challenging problem when revising a shoulder arthroplasty. Precise pre-operative planning based on plain radiographs or CT scans is essential. We have investigated a new radiological classification system to describe the degree of medialisation of the bony glenoid and that will indicate the amount of bone potentially available for supporting a glenoid component. It depends on the relationship between the most medial part of the articular surface of the glenoid with the base of the coracoid process and the spinoglenoid notch: it classifies the degree of bone loss into three types.

It also attempts to predict the type of glenoid reconstruction that may be possible (impaction bone grafting, structural grafting or simple non-augmented arthroplasty) and gives guidance about whether a pre-operative CT scan is indicated.

Aims

The primary aim of this study was to analyse the position of the acetabular and femoral components in total hip arthroplasty undertaken using an anterior surgical approach.