Intrapelvic migration of the acetabular component of a total hip replacement, with severe acetabular destruction making reconstruction impossible, is very rare. We present a patient in whom the component was removed using a laparotomy and a transperitoneal approach with subsequent salvage using a saddle prosthesis and a total femoral replacement.

We reviewed the initial post-operative radiographs of the Trident acetabulum and identified a problem with seating of the metal-backed ceramic liner. We identified 117 hips in 113 patients who had undergone primary total hip replacement using the Trident shell with a metal-backed alumina liner. Of these, 19 (16.4%) were noted to have incomplete seating of the liner, as judged by plain anteroposterior and lateral radiographs. One case of complete liner dissociation necessitating early revision was not included in the prevalence figures. One mis-seated liner was revised in the early post-operative period and two that were initially incompletely seated were found on follow-up radiographs to have become correctly seated. There may be technical issues with regard to the implanting of this prosthesis of which surgeons should be aware. However, there is the distinct possibility that the Trident shell deforms upon implantation, thereby preventing complete seating of the liner.

Disruption of the interosseous membrane is easily missed in patients with Essex-Lopresti syndrome. None of the imaging techniques available for diagnosing disruption of the interosseous membrane are completely dependable.

We undertook an investigation to identify whether a simple intra-operative test could be used to diagnose disruption of the interosseous membrane during surgery for fracture of the radial head and to see if the test was reproducible.

We studied 20 cadaveric forearms after excision of the radial head, ten with and ten without disruption of the interosseous membrane. On each forearm, we performed the radius joystick test: moderate lateral traction was applied to the radial neck with the forearm in maximal pronation, to look for lateral displacement of the proximal radius indicating that the interosseous membrane had been disrupted. Each of six surgeons (three junior and three senior) performed the test on two consecutive days.

Intra-observer agreement was 77% (95% confidence interval (CI) 67 to 85) and interobserver agreement was 97% (95% CI 92 to 100). Sensitivity was 100% (95% CI 97 to 100), specificity 88% (95% CI 81 to 93), positive predictive value 90% (95% CI 83 to 94), and negative predictive value 100%).

This cadaveric study suggests that the radius joystick test may be useful for detecting disruption of the interosseous membrane in patients undergoing open surgery for fracture of the radial head and is reproducible. A confirmatory study in vivo is now required.

We compared thromboembolic events, major haemorrhage and death after total hip replacement in patients receiving either aspirin or low-molecular-weight heparin (LMWH). We analysed data from the National Joint Registry for England and Wales linked to an administrative database of hospital admissions in the English National Health Service. A total of 108 584 patients operated on between April 2003 and September 2008 were included and followed up for 90 days. Multivariable risk modelling and propensity score matching were used to estimate odds ratios (OR) adjusted for baseline risk factors. An OR <  1 indicates that rates are lower with LMWH than with aspirin. In all, 21.1% of patients were prescribed aspirin and 78.9% LMWH. Without adjustment, we found no statistically significant differences. The rate of pulmonary embolism was 0.68% in both groups and 90-day mortality was 0.65% with aspirin and 0.61% with LMWH (OR 0.93; 95% CI 0.77 to 1.11). With risk adjustment, the difference in mortality increased (OR 0.84; 95% CI 0.69 to 1.01). With propensity score matching the mortality difference increased even further to 0.65% with aspirin and 0.51% with LMWH (OR 0.77; 95% CI 0.61 to 0.98). These results should be considered when the conflicting recommendations of existing guidelines for thromboprophylaxis after hip replacement are being addressed.

Recurrence of back or leg pain after discectomy is a well-recognised problem with an incidence of up to 28%. Once conservative measures have failed, several surgical options are available and have been tried with varying degrees of success. In this study, 42 patients with recurrent symptoms after discectomy underwent less invasive posterior lumbar interbody fusion (LI-PLIF). Clinical outcome was measured using the Oswestry Disability Index (ODI), Short Form 36 (SF-36) questionnaires and visual analogue scales for back (VAS-BP) and leg pain (VAS-LP). There was a statistically significant improvement in all outcome measures (p < 0.001). The debate around which procedure is the most effective for these patients remains controversial.

Our results show that LI-PLIF is as effective as any other surgical procedure. However, given that it is less invasive, we feel that it should be considered as the preferred option.

Metastatic epidural compression of the spinal cord is a significant source of morbidity in patients with systemic cancer. With improved oncological treatment, survival in these patients is improving and metastatic cord compression is encountered increasingly often. The treatment is mostly palliative. Surgical management involves early circumferential decompression of the cord with concomitant stabilisation of the spine. Patients with radiosensitive tumours without cord compression benefit from radiotherapy. Spinal stereotactic radiosurgery and minimally invasive techniques, such as vertebroplasty and kyphoplasty, with or without radiofrequency ablation, are promising options for treatment and are beginning to be used in selected patients with spinal metastases.

In this paper we review the surgical management of patients with metastatic epidural spinal cord compression.

We reviewed the results at nine to 13 years of 125 total hip replacements in 113 patients using the monoblock uncemented Morscher press-fit acetabular component. The mean age at the time of operation was 56.9 years (36 to 74). The mean clinical follow-up was 11 years (9.7 to 13.5) and the mean radiological follow-up was 9.4 years (7.7 to 13.1). Three hips were revised, one immediately for instability, one for excessive wear and one for deep infection.

No revisions were required for aseptic loosening. A total of eight hips (7.0%) had osteolytic lesions greater than 1 cm, in four around the acetabular component (3.5%). One required bone grafting behind a well-fixed implant. The mean wear rate was 0.11 mm/year (0.06 to 0.78) and was significantly higher in components with a steeper abduction angle.

Kaplan-Meier survival curves at 13 years showed survival of 96.8% (95% confidence interval 90.2 to 99.0) for revision for any cause and of 95.7% (95% confidence interval 88.6 to 98.4) for any acetabular re-operation.

Our aim in this prospective radiological study was to determine whether the flexibility rate calculated from radiographs obtained during forced traction under general anaesthesia, was better than that of fulcrum-bending radiographs before corrective surgery in predicting the extent of the available correction in patients with idiopathic scoliosis. We evaluated 33 patients with a Cobb angle > 60° on a standing posteroanterior radiograph, who had been treated by posterior correction. Pre-operative standing fulcrum-bending radiographs and those with forced-traction under general anaesthesia were obtained. Post-operative standing radiographs were taken after surgical correction.

The mean forced-traction flexibility rate was 55% (sd 11.3) which was significantly higher than the mean fulcrum-bending flexibility rate of 32% (sd 16.1) (p < 0.001). We found no correlation between either the forced-traction or fulcrum-bending flexibility rates and the correction rate post-operatively (p = 0.24 and p = 0.44, respectively).

Radiographs obtained during forced traction under general anaesthesia were better at predicting the flexibility of the curve than fulcrum-bending radiographs in curves with a Cobb angle > 60° in the standing position and may identify those patients for whom supplementary anterior surgery can be avoided.

We have reviewed our experience in managing 11 patients who sustained an indirect sternal fracture in combination with an upper thoracic spinal injury between 2003 and 2006. These fractures have previously been described as ‘associated’ fractures, but since the upper thorax is an anatomical entity composed of the upper thoracic spine, ribs and sternum joined together, we feel that the term ‘fractures of the upper transthoracic cage’ is a better description. These injuries are a challenge because they are unusual and easily overlooked. They require a systematic clinical and radiological examination to identify both lesions. This high-energy trauma gives severe devastating concomitant injuries and CT with contrast and reconstruction is essential after resuscitation to confirm the presence of all the lesions. The injury level occurs principally at T4–T5 and at the manubriosternal joint. These unstable fractures need early posterior stabilisation and fusion or, if treated conservatively, a very close follow-up.

We studied, ten patients (11 elbows) who had undergone 14 allograft-prosthesis composite reconstructions following failure of a previous total elbow replacement with massive structural bone loss. There were nine women and one man with a mean age of 64 years (40 to 84), who were reviewed at a mean of 75 months (24 to 213). One patient developed a deep infection after 26 months and had the allograft-prosthesis composite removed, and two patients had mild pain. The median flexion-extension arc was 100° (95% confidence interval (CI) 76° to 124°). With the exception of the patient who had the infected failure, all the patients could use their elbows comfortably without splints or braces for activities of daily living. The mean Mayo Elbow Performance Index improved from 9.5 (95% CI 4.4 to 14.7) pre-operatively to 74 (95% CI 62.4 to 84.9) at final review.

Radiologically, the rate of partial resorption was similar in the humeral and ulnar allografts (three of six and four of eight, respectively; p > 0.999). The patterns of resorption, however, were different. Union at the host-bone-allograft junction was also different between the humeral and ulnar allografts (one of six and seven of eight showing union, respectively; p = 0.03).

At medium-term follow-up, allograft-prosthesis composite reconstruction appears to be a useful salvage technique for failed elbow replacements with massive bone loss. The effects of allograft resorption and host-bone-allograft junctional union on the longevity of allograft-prosthesis composite reconstruction, however, remain unknown, and it is our view that these patients should remain under long-term regular review.

Muscle atrophy has been demonstrated in patients suffering from osteoarthritis of the hip, but little is known about muscular recovery after total hip replacement (THR). A total of 20 patients with unilateral osteoarthritis of the hip were assessed before, six months and two years after THR. The cross-sectional area and radiological density of the muscles of the hip, thigh, calf and back were measured using CT. We hypothesised that the muscles would not recover fully after operation.

After two years comparison of the limb with the THR with the healthy limb showed that there was such a reduction in the cross-sectional area in iliopsoas (7.0%; p = 0.006) and the hip adductors (8.4%, p = 0.003) and in the radiological density in gluteus maximus (10.1 Hounsfield units; p < 0.001), gluteus medius/minimus (5.6 Hounsfield units; p = 0.011), iliopsoas (3.9 Hounsfield units; p < 0.001) and the adductors (2.4 Hounsfield units; p = 0.022).

Thus, there was persistent muscle atrophy in muscles acting about the hip two years after THR. We suggest that an earlier operation or a more intensive rehabilitation may reverse these changes.

Orientation of the native acetabular plane as defined by the transverse acetabular ligament (TAL) and the posterior labrum was measured intra-operatively using computer-assisted navigation in 39 hips. In order to assess the influence of alignment on impingement, the range of movement was calculated for that defined by the TAL and the posterior labrum and compared with a standard acetabular component position (abduction 45°/anteversion 15°).

With respect to the registration of the plane defined by the TAL and the posterior labrum, there was moderate interobserver agreement (r = 0.64, p < 0.001) and intra-observer reproducibility (r = 0.73, p < 0.001). The mean acetabular component orientation achieved was abduction of 41° (32° to 51°) and anteversion of 18° (−1° to 36°). With respect to the Lewinnek safe zone (abduction 40° ±10°, anteversion 15° ±10°), 35 of the 39 acetabular components were within this zone. However, there was no improvement in the range of movement (p = 0.94) and no significant difference in impingement (p = 0.085).

Alignment of the acetabular component with the TAL and the posterior labrum might reduce the variability of acetabular component placement in total hip replacement. However, there is only a moderate interobserver agreement and intra-observer reliability in the alignment of the acetabular component using the TAL and the posterior labrum. No reduction in impingement was found when the acetabular component was aligned with the TAL and the posterior labrum, compared with a standard acetabular component position.

The operative treatment of displaced fractures of the tibial plateau is challenging. Recent developments in the techniques of internal fixation, including the development of locked plating and minimal invasive techniques have changed the treatment of these fractures. We review current surgical approaches and techniques, improved devices for internal fixation and the clinical outcome after utilisation of new methods for locked plating.

The presacral retroperitoneal approach for axial lumbar interbody fusion (presacral ALIF) is not widely reported, particularly with regard to the mid-term outcome. This prospective study describes the clinical outcomes, complications and rates of fusion at a follow-up of two years for 26 patients who underwent this minimally invasive technique along with further stabilisation using pedicle screws. The fusion was single-level at the L5-S1 spinal segment in 17 patients and two-level at L4–5 and L5-S1 in the other nine. The visual analogue scale for pain and Oswestry Disability Index scores were recorded pre-operatively and during the 24-month study period. The evaluation of fusion was by thin-cut CT scans at six and 12 months, and flexion-extension plain radiographs at six, 12 and 24 months. Significant reductions in pain and disability occurred as early as three weeks postoperatively and were maintained. Fusion was achieved in 22 of 24 patients (92%) at 12 months and in 23 patients (96%) at 24 months. One patient (4%) with a pseudarthrosis underwent successful revision by augmentation of the posterolateral fusion mass through a standard open midline approach.

There were no severe adverse events associated with presacral ALIF, which in this series demonstrated clinical outcomes and fusion rates comparable with those of reports of other methods of interbody fusion.

Injury to the sciatic nerve following closed manipulation of a dislocated total hip replacement is rare. We present such a case in an elderly patient with partial recovery following exploration and release of the nerve.

Between March 2000 and February 2006, we carried out a prospective study of 100 patients with a low-grade isthmic spondylolisthesis (Meyerding grade II or below), who were randomised to receive a single-level and instrumented posterior lumbar interbody fusion with either one or two cages. The minimum follow-up was for two years. At this stage 91 patients were available for review. A total of 47 patients received one cage (group 1) and 44 two cages (group 2). The clinical and radiological outcomes of the two groups were compared.

There were no significant differences between the two groups in terms of post-operative pain, Oswestry Disability Score, clinical results, complication rate, percentage of post-operative slip, anterior fusion rate or posterior fusion rate. On the other hand, the mean operating time was 144 minutes (100 to 240) for patients in group 1 and 167 minutes (110 to 270) for those in group 2 (p = 0.0002). The mean blood loss up to the end of the first post-operative day was 756 ml (510 to 1440) in group 1 and 817 ml (620 to 1730) in group 2 (p < 0.0001).

Our results suggest that an instrumented posterior lumbar interbody fusion performed with either one or two cages in addition to a bone graft around the cage has a low rate of complications and a high fusion rate. The clinical outcomes were good in most cases, regardless of whether one or two cages had been used.

We assessed leg length discrepancy and hip function in 90 patients undergoing primary total hip arthroplasty before surgery and at three and 12 months after. Function was measured using the Oxford hip score (OHS). After surgery the mean OHS improved by 26 points after three months and by 30 points after 12.

After operation 56 (62%) limbs were long by a mean of 9 mm and this was perceived by 24 (43%) patients after three months and by 18 (33%) after 12. The mean OHS in patients who perceived true lengthening was 27% worse than the rest of the population after three months and 18% worse after 12. In 55 (98%) patients, lengthening occurred in the femoral component. Appropriate placement of the femoral component could significantly reduce a patient’s perception of discrepancy of length.

Pre-operative computerised three-dimensional planning was carried out in 223 patients undergoing total hip replacement with a cementless acetabular component and a cementless modular-neck femoral stem. Components were chosen which best restored leg length and femoral offset. The post-operative restoration of the anatomy was assessed by CT and compared with the pre-operative plan.

The component implanted was the same as that planned in 86% of the hips for the acetabular implant, 94% for the stem, and 93% for the neck-shaft angle. The rotational centre of the hip was restored with a mean accuracy of 0.73 mm (sd 3.5) craniocaudally and 1.2 mm (sd 2) laterally. Limb length was restored with a mean accuracy of 0.3 mm (sd 3.3) and femoral offset with a mean accuracy of 0.8 mm (sd 3.1).

This method appears to offer high accuracy in hip reconstruction as the difficulties likely to be encountered when restoring the anatomy can be anticipated and solved pre-operatively by optimising the selection of implants. Modularity of the femoral neck helped to restore the femoral offset and limb length.

The inferior gluteal artery is described in standard anatomy textbooks as contributing to the blood supply of the hip through an anastomosis with the medial femoral circumflex artery. The site(s) of the anastomosis has not been described previously. We undertook an injection study to define the anastomotic connections between these two arteries and to determine whether the inferior gluteal artery could supply the lateral epiphyseal arteries alone. From eight fresh-frozen cadaver pelvic specimens we were able to inject the vessels in 14 hips with latex moulding compound through either the medial femoral circumflex artery or the inferior gluteal artery. Injected vessels around the hip were then carefully exposed and documented photographically.

In seven of the eight specimens a clear anastomosis was shown between the two arteries adjacent to the tendon of obturator externus. The terminal vessel arising from this anastomosis was noted to pass directly beneath the posterior capsule of the hip before ascending the superior aspect of the femoral neck and terminating in the lateral epiphyseal vessels. At no point was the terminal vessel found between the capsule and the conjoined tendon. The medial femoral circumflex artery receives a direct supply from the inferior gluteal artery immediately before passing beneath the capsule of the hip.

Detailed knowledge of this anatomy may help to explain the development of avascular necrosis after hip trauma, as well as to allow additional safe surgical exposure of the femoral neck and head.

We present a 25-year-old patient with juvenile rheumatoid arthritis and ankylosis of both hips and both knees treated by staged bilateral hip and knee arthroplasty. She was followed up for 18 months. We discuss the pre-operative planning, surgical details and post-operative rehabilitation.