INTRODUCTION. A detailed clinical examination and investigations are required to evaluate the cause of persisting groin pain following a metal on metal (MoM) hip replacement. Adverse reaction to metallic debris (ARMD) is an emerging problem with MoM hip replacements. It is an umbrella term encompassing metallosis, pseudo-tumors and aseptic lymphocytic vasculitis associated lesions (ALVAL). The role of imaging in the diagnosis of this complex problem is still unclear. A study was undertaken to evaluate the efficacy of ultrasound in diagnosis of ARMD following a MoM hip replacement. METHODS. The study group included 35 patients with a clinical and histological diagnosis of ARMD, who had a preoperative ultrasound. All ultrasound procedures were performed on the anterior and lateral aspects of the painful hip with a high frequency probe of 9–13 MHz (Sonoline Antares – Siemens). RESULTS. All patients diagnosed with ARMD had abnormalities identified on ultrasound. Fluid inside the joint was noted in 30 out of 35 procedures (85.7 %). Fluid outside the joint was noted in 33 procedures (94.3 %). Amongst the patients with fluid outside the joint, 32 had iliopsoas and 30 had trochanteric bursitis. Echogenic reflections were noted in 31 out of 35 procedures (88.6 %). Considerable attenuation or absence of iliopsoas and gluteus tendon reflection was seen in many patients with echogenic fluid collections on the anterior and trochanteric aspects of hip. Progression of such changes was noted on further 5 patients, who had a repeat ultrasound within an interval of 3–6 months. 1 patient had a progression from anechogenic to echogenic joint effusion. DISCUSSION. Different radiological investigations including MRI scan have been used for evaluation of painful MoM hip arthroplasty. To our knowledge, this is the first study to demonstrate the efficacy of ultrasound in diagnosis of ARMD. Floating echogenic reflections and fluid collections around iliopsoas and gluteus medius/minimus tendons is highly suggestive of ARMD. Ultrasound is a cheap, non-invasive and dynamic investigation and has been shown to be reliable in diagnosis of ARMD

Introduction. Our classic outcome scores increasingly fail to distinguish interventions or to reflect rising patient demands. Scores are subjective, have a low ceiling and score pain rather than function. Objective functional assessment tools for routine clinical use are required. This study validates inertial sensor motion analysis (IMA) by differentiating patients with knee versus hip osteoarthritis in a block-step test. Methods. Step up and down from a block (h=20cm, 3 repetitions) loading the affected (A) and unaffected (UA) leg was measured in n=59 subjects using a small inertial sensor (3D gyro and accelerometer, m=39g) attached onto the sacrum. Patients indicated for either primary unilateral THA (n=20; m/f=4/6, age=69.4yrs ±9.8) or TKA (n=16;m/f=7/9;age=67.8yrs ±8.2) were compared to healthy controls (n=23;m/f=13/10;age=61.7yrs ±6.2) and between each other to validate the test's capacity for diagnostics and as an outcome measure. The motion parameters derived (semi-) automatically in Matlab for both legs were: front-back (FB-) sway and left-right (LR-) sway (up and down); peak-to-peak accelerations (Acc) during step down. In addition the asymmetry between both legs (ASS) was calculated for each parameter. Group differences were tested (t-test) and the diagnostic value determined by the area under the curve (AUC) of the ROC-curve. Results. During step-up FB-sway was higher for THA (20.4°±4.9) and TKA (21.7°±5.9) patients than for healthy controls (15.5°±3.4, p<0.001). Also asymmetry was higher (THA=20%, TKA=21%, H=11%, p<0.001). Results were similar during step down except for the affected leg of THA patients where FB-sway (THA=16.2°±3.0) was similar to controls but sign. different to TKA patients (22.2±4.4) producing a high diagnostic power (AUC=0.88) to differentiate THA and TKA. LR-sway was also indicative for THA patients being the only subjects showing high asymmetry between the legs (A=14.3°±3.7 vs UA=11.9°±3.1, p<0.001). Acceleration during step-down asymmetric in patients, especially in THA (H<TKA<THA;p<0.05; AUC=0.87). Discussion. The IMA-block-step test could detect pathology specific compensation mechanism: During step-up patients use more FB-sway (+29%) to generate momentum for compensating muscle weakness and decrease joint loading. During step-down, only THA patients showed less FB-sway with their affected leg avoiding the painful hip flexion. Also in THA the LR-sway was higher in the affected than unaffected side due to the typical abductor weakness and resulting Trendelenburg sign. The IMA-block-step test could objectify compensation mechanisms used in OA and showed the power to differentiate between H, TKA and THA. It is low cost and fast to perform (<5min) by non-specialist personnel and thus could be used in clinical routine to supplement questionnaire based outcome scores

In the time since Letournel popularised the surgical treatment of acetabular fractures, more than 25 years ago, there have been many changes within the field, related to patients, surgical technique, implants and post-operative care. However, the long-term outcomes appear largely unchanged. Does this represent stasis or have the advances been mitigated by other negative factors? In this article we have attempted to document the recent changes within the surgery of patients with a fracture involving the acetabulum, outline contemporary management, and identify the major problem areas where further research is most needed.

Cite this article: Bone Joint J 2017;99-B:1125–31

United Kingdom National Institute for Health and Clinical Excellence guidelines recommend the use of total hip replacement (THR) for displaced intracapsular fractures of the femoral neck in cognitively intact patients, who were independently mobile prior to the injury. This study aimed to analyse the risk factors associated with revision of the implant and mortality following THR, and to quantify risk. National Joint Registry data recording a THR performed for acute fracture of the femoral neck between 2003 and 2010 were analysed. Cox proportional hazards models were used to investigate the extent to which risk of revision was related to specific covariates. Multivariable logistic regression was used to analyse factors affecting peri-operative mortality (< 90 days). A total of 4323 procedures were studied. There were 80 patients who had undergone revision surgery at the time of censoring (five-year revision rate 3.25%, 95% confidence interval 2.44 to 4.07) and 137 patients (3.2%) patients died within 90 days. After adjusting for patient and surgeon characteristics, an increased risk of revision was associated with the use of cementless prostheses compared with cemented (hazard ratio (HR) 1.33, p = 0.021). Revision was independent of bearing surface and head size. The risk of mortality within 90 days was significantly increased with higher American Society of Anesthesiologists (ASA) grade (grade 3: odds ratio (OR) 4.04, p < 0.001; grade 4/5: OR 20.26, p < 0.001; both compared with grades 1/2) and older age (≥ 75 years: OR 1.65, p = 0.025), but reduced over the study period (9% relative risk reduction per year).

THR is a good option in patients aged < 75 years and with ASA 1/2. Cementation of the femoral component does not adversely affect peri-operative mortality but improves survival of the implant in the mid-term when compared with cementless femoral components. There are no benefits of using head sizes > 28 mm or bearings other than metal-on-polyethylene. More research is required to determine the benefits of THR over hemiarthroplasty in older patients and those with ASA grades > 2.