Introduction

The pathogenesis of rotator cuff disease (RCD) is complex and not fully understood. This systematic review set out to summarise the histological and molecular changes that occur throughout the spectrum of RCD.

We examined the relationships between the serum levels of chromium and cobalt ions and the inclination angle of the acetabular component and the level of activity in 214 patients implanted with a metal-on-metal resurfacing hip replacement. Each patient had a single resurfacing and no other metal in their body. All serum measurements were performed at a minimum of one year after operation. The inclination of the acetabular component was considered to be steep if the abduction angle was greater than 55°.

There were significantly higher levels of metal ions in patients with steeply-inclined components (p = 0.002 for chromium, p = 0.003 for cobalt), but no correlation was found between the level of activity and the concentration of metal ions. A highly significant (p < 0.001) correlation with the arc of cover was found. Arcs of cover of less than 10 mm were correlated with a greater risk of high concentrations of serum metal ions. The arc of coverage was also related to the design of the component and to size as well as to the abduction angle of the acetabular component. Steeply-inclined acetabular components, with abduction angles greater than 55°, combined with a small size of component are likely to give rise to higher serum levels of cobalt and chromium ions. This is probably due to a greater risk of edge-loading.

We report the use of porous metal acetabular revision shells in the treatment of contained bone loss. The outcomes of 53 patients with ≤ 50% acetabular bleeding host bone contact were compared with a control group of 49 patients with > 50% to 85% bleeding host bone contact. All patients were treated with the same type of trabecular metal acetabular revision shell. The mean age at revision was 62.4 years (42 to 80) and the mean follow-up of both groups was 72.4 months (60 to 102). Clinical, radiological and functional outcomes were assessed. There were four (7.5%) mechanical failures in the ≤ 50% host bone contact group and no failures in the > 50% host bone contact group (p = 0.068). Out of both groups combined there were four infections (3.9%) and five recurrent dislocations (4.9%) with a stable acetabular component construct that were revised to a constrained liner. Given the complexity of the reconstructive challenge, porous metal revision acetabular shells show acceptable failure rates at five to ten years’ follow-up in the setting of significant contained bone defects. This favourable outcome might be due to the improved initial stability achieved by a high coefficient of friction between the acetabular implant and the host bone, and the high porosity, which affords good bone ingrowth.

Secure fixation of displaced proximal fractures of the humerus is a challenging problem. A total of 32 patients with acutely displaced three- or four-part proximal fractures of the humerus were treated by open reduction and internal fixation using the proximal humeral internal locking system (PHILOS) plate. There were 23 women and nine men with a mean age of 59.9 years (18 to 87). Data were collected prospectively and the outcomes were assessed using the Constant score. The mean follow-up was for 11 months (3 to 24). In 31 patients (97%) the fracture united clinically and radiologically at a mean of 10 weeks (8 to 24). The mean Constant score at final review was 66.5 (30 to 92). There was no significant difference in outcome when comparing patients aged more than 60 years (18 patients) with those aged less than 60 years (14 patients) (t-test, p = 0.8443). There was one case each of nonunion, malunion and a broken screw in the elderly population.

This plate provides an alternative method of fixation for fractures of the proximal humerus. It provides a stable fixation in young patients with good-quality bone sufficient to permit early mobilisation. Failure of the screws to maintain fixation in the elderly remains a problem.

The effect of timing of a manipulation under anaesthetic (MUA) and injection of corticosteroid and local anaesthetic for the treatment of frozen shoulder has attracted little attention to date. All studies describe a period of conservative treatment before proceeding to an MUA. Delay has been associated with a poorer outcome.

We present a retrospective review of a prospectively collected, single-surgeon, consecutive series of 246 patients with a primary frozen shoulder treated by MUA within four weeks of presentation. The mean duration of presenting symptoms was 28 weeks (6 to 156), and time to initial post-operative assessment was 26 days (5 to 126). The Oxford shoulder score (OSS) improved by a mean of 16 points (Wilcoxon signed-ranks test, p < 0.001) with a mean OSS at this time of 43 (7 to 48). Linear regression analysis showed no correlation between the duration of presenting symptoms and OSS at initial follow-up (R2 < 0.001) or peri-operative change in OSS (R2 < 0.001) or OSS at long-term follow-up (R2 < 0.03). Further analysis at a mean of 42 months (8 to 127) revealed a sustained improvement with a mean OSS of 44 (16 to 48).

A good outcome follows an MUA and injection of corticosteroid and local anaesthetic in patients with primary frozen shoulder, independent of the duration of the presenting symptoms, and this improvement is maintained in the long term.

The role of inflammatory cells and their products in tendinopathy is not completely understood. Pro-inflammatory cytokines are upregulated after oxidative and other forms of stress. Based on observations that increased cytokine expression has been demonstrated in cyclically-loaded tendon cells we hypothesised that because of their role in oxidative stress and apoptosis, pro-inflammatory cytokines may be present in rodent and human models of tendinopathy. A rat supraspinatus tendinopathy model produced by running overuse was investigated at the genetic level by custom micro-arrays. Additionally, samples of torn supraspinatus tendon and matched intact subscapularis tendon were collected from patients undergoing arthroscopic shoulder surgery for rotator-cuff tears and control samples of subscapularis tendon from ten patients with normal rotator cuffs undergoing arthroscopic stabilisation of the shoulder were also obtained. These were all evaluated using semiquantitative reverse transcription polymerase chain-reaction and immunohistochemistry.

We identified significant upregulation of pro-inflammatory cytokines and apoptotic genes in the rodent model (p = 0.005). We further confirmed significantly increased levels of cytokine and apoptotic genes in human supraspinatus and subscapularis tendon harvested from patients with rotator cuff tears (p = 0.0008).

These findings suggest that pro-inflammatory cytokines may play a role in tendinopathy and may provide a target for preventing tendinopathies.

Fractures of the proximal humerus with concomitant vascular injury are rare in children. We describe the presentation, diagnosis, and treatment of a fracture of the proximal humerus in association with an axillary artery injury in a child.

We identified 16 patients with a mean age of 56.5 years (31 to 86) from a large consecutive series of patients with proximal humeral fractures over a 15-year period, who had sustained a fracture with skin compromise after a blunt injury. The study group represented 0.2% of 7825 proximal humeral fractures treated during this period and all had a displaced Neer two-part fracture pattern. Two patterns of skin injury were identified: in ten patients there was skin penetration at the time of the original injury, and the other six patients initially had closed injuries. These six patients had fracture fragments penetrating the muscular envelope to lie subcutaneously producing either early skin tethering (two patients) or delayed skin penetration and sinus formation (four patients). The pattern of injury to the soft-tissue envelope and the fracture pattern were similar for all injuries. Treatment of these injuries was determined by the initial severity of the soft-tissue injury and the medical status of the patient. We currently favour open reduction and internal fixation of these fractures wherever possible, owing to the high rate of nonunion with non-operative management.

Modern metal-on-metal hip resurfacing has been widely performed in the United Kingdom for over a decade. However, the literature reports conflicting views of the benefits: excellent medium- to long-term results with some brands in specific subgroups, but high failure rates and local soft-tissue reactions in others. The National Joint Registry for England and Wales (NJR) has collected data on all hip resurfacings performed since 2003. This retrospective cohort study recorded survival time to revision from a resurfacing procedure, exploring risk factors independently associated with failure. All patients with a primary diagnosis of osteoarthritis who underwent resurfacing between 2003 and 2010 were included in the analyses. Cox’s proportional hazard models were used to analyse the extent to which the risk of revision was related to patient, surgeon and implant covariates.

A total of 27 971 hip resurfacings were performed during the study period, of which 1003 (3.59%) underwent revision surgery. In the final adjusted model, we found that women were at greater risk of revision than men (hazard ratio (HR) = 1.30, p = 0.007), but the risk of revision was independent of age. Of the implant-specific predictors, five brands had a significantly greater risk of revision than the Birmingham Hip Resurfacing (BHR) (ASR: HR = 2.82, p < 0.001, Conserve: HR = 2.03, p < 0.001, Cormet: HR = 1.43, p = 0.001, Durom: HR = 1.67, p < 0.001, Recap: HR = 1.58, p = 0.007). Smaller femoral head components were also significantly more likely to require revision (≤ 44 mm: HR = 2.14, p < 0.001, 45 to 47 mm: HR = 1.48, p = 0.001) than medium or large heads, as were operations performed by low-volume surgeons (HR = 1.36, p <  0.001). Once these influences had been removed, in 4873 male patients < 60 years old undergoing resurfacing with a BHR, the five-year estimated risk of revision was 1.59%.

In summary, after adjustment for a range of covariates we found that there were significant differences in the rate of failure between brands and component sizes. Younger male patients had good five-year implant survival when the BHR was used.

The epidemiological data and intra-operative findings from 260 consecutive arthroscopically-diagnosed acetabular labral tears seen over a ten-year period were analysed. Radiographs of 128 of these patients were assessed for dysplasia using established radiological parameters. Patients with acetabular dysplasia were then compared against those without in order to identify any differences in gender, age, the side of the tear, the pattern of the tear, the number of quadrants involved, the quadrant preference and the prevalence of intra-articular comorbidity. Dysplasia was found in 46% (59 of 128) of the hips. No significant differences existed between the dysplastic and non-dysplastic subgroups as regards gender distribution, the side of the lesion, the number of quadrants involved or the distribution of tears among the quadrants. However, tears associated with dysplasia were diagnosed in an older age group, had a different pattern and were associated with a much higher prevalence of osteoarthritis.

In an adult man the mean femoral anteversion angle measures approximately 15°, for which the reasons have never been fully elucidated.

An assortment of simian and quadruped mammalian femora was therefore examined and the anteversion angles measured. A simple static mathematical model was then produced to explain the forces acting on the neck of the femur in the quadruped and in man. Femoral anteversion was present in all the simian and quadruped femora and ranged between 4° and 41°. It thus appears that man has retained this feature despite evolving from quadrupedal locomotion.

Quadrupeds generally mobilise with their hips flexed forwards from the vertical; in this position, it is clear that anteversion gives biomechanical advantage against predominantly vertical forces. In man with mobilisation on vertical femora, the biomechanical advantage of anteversion is against forces acting mainly in the horizontal plane. This has implications in regard to the orientation of hip replacements.

We compared the orientation of the acetabular component obtained by a conventional manual technique with that using five different navigation systems.

Three surgeons carried out five implantations of an acetabular component with each navigation system, as well as manually, using an anatomical model. The orientation of the acetabular component, including inclination and anteversion, and its position was determined using a co-ordinate measuring machine.

The variation of the orientation of the acetabular component was higher in the conventional group compared with the navigated group. One experienced surgeon took significantly less time for the procedure. However, his placement of the component was no better than that of the less experienced surgeons. Significantly better inclination and anteversion (p < 0.001 for both) were obtained using navigation. These parameters were not significantly different between the surgeons when using the conventional technique (p = 0.966).

The use of computer navigation helps a surgeon to orientate the acetabular component with less variation regarding inclination and anteversion.

Our aim was to assess the intra- and inter-observer reliability in the establishment of the anterior pelvic plane used in imageless computer-assisted navigation. From this we determined the subsequent effects on version and inclination of the acetabular component.

A cadaver model was developed with a specifically-designed rod which held the component tracker at a fixed orientation to the pelvis, leaving the anterior pelvic plane as the only variable. Eight surgeons determined the anterior pelvic plane by palpating and registering the bony landmarks as reference points. The exact anterior pelvic plane was then established by using anatomically-placed bone screws as reference points.

The difference between the surgeons was found to be highly significant (p < 0.001). The variation was significantly larger for anteversion (sd 9.6°) than for inclination (sd 6.3°). The present method for registering pelvic landmarks shows significant inaccuracy, which highlights the need for improved methods of registration before this technique is considered to be safe.

Developmental dysplasia of the hip predisposes to premature degenerative hip disease. A number of operations have been described to improve acetabular cover and have achieved varying degrees of success. We present the case of an 84-year-old woman, who underwent a shelf procedure to reconstruct a dysplastic hip 75 years ago. To date, the shelf remains intact and the hip is asymptomatic. We believe this represents the longest documented outcome of any procedure to stabilise the hip.

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.

Narrowing of the femoral neck after resurfacing arthroplasty of the hip has been described previously in both cemented and uncemented hip resurfacing. The natural history of narrowing of the femoral neck is unknown. We retrospectively measured the diameter of the femoral neck in a series of 163 Birmingham hip resurfacings in 163 patients up to a maximum of six years after operation to determine the extent and progression of narrowing.

There were 105 men and 58 women with a mean age of 52 years (18 to 82). At a mean follow-up of five years, the mean Harris hip score was 94.8 (47 to 100) and the mean flexion of the hip 112.5° (80° to 160°). There was some narrowing of the femoral neck in 77% (125) of the patients reviewed, and in 27.6% (45) the narrowing exceeded 10% of the diameter of the neck. A multiple logistic regression analysis showed a significant association (chi-squared test (derived from logistic regression) p = 0.01) of narrowing with female gender and a valgus femoral neck/shaft angle. There was no significant association between the range of movement, position or size of the component or radiological lucent lines and narrowing of the neck (chi-squared test; p = 0.10 (flexion), p = 0.08 (size of femoral component), p = 0.09 (size of acetabular component), p = 0.71 (femoral component angulation), p = 0.99 (lucent lines)). There was no significant difference between the diameter of the neck at a mean of three years (2.5 to 3.5) and that at five years (4.5 to 5.5), indicating that any change in the diameter of the neck had stabilised by three years (sign rank test, p = 0.60).

We conclude that narrowing of the femoral neck which is found with the Birmingham hip resurfacing arthroplasty is in most cases associated with no adverse clinical or radiological outcome up to a maximum of six years after the initial operation.

We examined the placement of the stem in relation to the medial tibial cortex when using total knee replacements (TKRs) with medially-offset tibial stems in Korean patients. Measurements were performed on the pre- and post-operative radiographs of 246 osteoarthritic knees replaced between January 2005 and May 2006 using the Genesis II or E-motion TKR with a medially-offset stem. Pre-operatively, we measured the distance between the mechanical axis and that of the tibial shaft and post-operatively, that between the midline of the tibial stem and the axis of the shaft.

Knees were identified in which there was radiological contact between the tip of the stem and the medial tibial cortex. The mechanical axis was located medial to the axis of the shaft in 203 knees (82.5%). Post-operatively, the midline of the tibial stem was located medial to the tibial shaft axis in 196 knees (79.7%). In 16 knees (6.5%) there was radiological contact between the tibial stem or cement mantle and the medial tibial cortex.

Our study has shown that the medially-offset stem in the tibial component may not be a good option for knees undergoing replacement for advanced osteoarthritis in some Korean patients.

We retrospectively studied 14 patients with proximal and diaphyseal tumours and disappearing bone (Gorham’s) disease of the humerus treated with wide resection and reconstruction using an allograft-resurfacing composite (ARC). There were ten women and four men, with a mean age of 35 years (8 to 69). At a mean follow-up of 25 months (10 to 89), two patients had a fracture of the allograft. In one of these it was revised with a similar ARC and in the other with an intercalary prosthesis. A further patient had an infection and a fracture of the allograft that was revised with a megaprosthesis. In all patients with an ARC, healing of the ARC-host bone interface was observed. One patient had failure of the locking mechanism of the total elbow replacement. The mean post-operative Musculoskeletal Tumor Society score for the upper extremity was 77% (46.7% to 86.7%), which represents good and excellent results; one patient had a poor result (46.7%).

In the short term ARC effectively relieves pain and restores shoulder function in patients with wide resection of the proximal humerus. Fracture and infection remain significant complications.

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.