Total joint arthroplasty (TJA) is one of the commonest and most successful orthopaedic procedures used for the management of end-stage arthritis. With the recent introduction of robotic-assisted joint replacement, Computed tomography (CT) has become part of required pre-operative planning.

The aim of this study is to quantify and characterise incidental CT findings, their clinical significance, and their effect on the planned joint arthroplasty.

All consecutive patients undergoing an elective TJA (total joint arthroplasty; hip or knee) were retrospectively identified, over a 4-year period (December 2019 and November 2023). Data documented and analysed included patient demographics, type of joint arthroplasty, CT findings, their clinical significance, as well as potential delays to the planned arthroplasty because of these findings and subsequent further investigation.

A total of 987 patients (female: 514 patients (52.1%)) undergoing TJA were identified (THA: 444 patients (45.0%); TKA: 400 patients (40.5%); UKA: 143 patients (14.5%)). Incidental findings within imaged areas were identified in 227 patients (23.0%). Of these findings, 74 (7.5%) were significant, requiring further investigation or management, 40 (4.1%) of which represented potential malignancy and 4 (0.4%) resulting in a new cancer diagnosis. A single patient was found to have an aneurysm requiring urgent vascular intervention. Surgery was delayed for further investigation in 4 patients (0.4%). Significant findings were more frequent in THA patients (THA: 43 (9.7%) TKA/UKA: 31 (5.7%)

Within our cohort, 74 (7.5%) patients had significant incidental findings that required further investigations or management, with 4 (0.4%) having a previously undiagnosed malignancy. We strongly advocate that all robotic arthroplasty planning CTs are reviewed and reported by a specialist, to avoid missing undiagnosed malignancies and other significant diagnoses.

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Joint replacement is a life-enhancing, cost-effective surgical intervention widely used to treat disabling joint pain mainly caused by osteoarthritis. Hip and knee joint replacements are common, highly successful operations bringing many patients relief from pain, and improve mobility.

Prosthetic joint infections (PJI) are often difficult to diagnose; diagnosis often relying on a combination of clinical findings, microbiological data and histological evaluation of periprosthetic tissue. The majority of recent studies demonstrate a higher sensitivity for the culture of sonication fluid (62–94%) than periprosthetic tissue (55–88%).

The Royal Devon & Exeter NHS Foundation Trust provided a specialist multidisciplinary team. We evaluated the use of sonication for identifying pathogens during revision hip and knee replacement in our unit with the intention of applying for further grants to study this technology in more detail; it was a diagnostic feasibility study. The target recruitment was 50 patients; 25 consecutive patients undergoing revision hip arthroplasty for any reason, and 25 undergoing revision knee arthroplasty for any reason. The majority of patients were identified in outpatient clinics.

Our results show that tissue culture remains more sensitive than sonication. The sensitivity for direct sonication was 75% compared with 80% for tissue culture; sensitivity of enriched sonication was 80 %, compared to the unit results for tissue culture of 83%. The combined sensitivity of tissue culture was better as a higher number of tissue specimens were obtained.

The different methodology might explain reported differences between this and other studies; however, our study does not support the use of sonication as the only tool in the diagnosis of PJI.

The use of spinal anesthesia with adjuvant intra-thecal opioids has been commonly used in total knee arthroplasty without documented clinical benefit. It has been associated with a potential increase in side effects, including nausea, vomiting, pruritus, urinary retention and oxygen usage. This double-blinded RCT investigated whether the addition of epimorph to spinal anesthesia in patients undergoing total knee arthroplasty resulted in superior pain control and decreased narcotic consumption without also causing an increase in postoperative complication rates.

We performed a prospective double-blind trial in patients undergoing primary total knee arthroplasty (TKA). Patients were randomised to receive either spinal anesthesia alone or spinal anesthesia with epimorph (150 ug). All patients received infiltration of a local anesthetic cocktail intraoperatively. Both the study patients and staff measuring outcomes were blinded to the experimental treatment received during data collection. Postoperatively, visual analogue scale (VAS) for pain was recorded at 6, 12, 18, 24, 36 and 48hrs and a final value at 1 week. Narcotic use, Foley insertion, oxygen requirements, nausea, vomiting and pruritus were recorded during the course of hospitalisation.

Forty-one patients were randomised into each of the spinal with epimorph and spinal alone treatment arms. The groups showed no significant differences in BMI, age, and gender distribution. In the first 12 hours postoperatively there was no difference in VAS for pain between the two groups, however there were significantly lower pain scores in the spinal alone patients at 18 hours (p=0.002), 24 hours (p=0.04) and 48 hours (p = 0.03) compared to the spinal with epimorph group. Narcotic usage was greater in the spinal group during the first 6 hours postoperatively, but beyond this time point narcotic usage was similar between the two groups. Additionally, there was a statistically significant increase in rate of complications with spinal epimorph including nausea (p=0.037) and pruritus (p=0.024). The incidence of urinary retention was greater in the spinal epimorph group, however this did not reach statistical significance.

This study demonstrates no clinical benefit with the addition of intra-thecal opioids to spinal anesthetic in primary TKA. In addition to a failing to reduce VAS pain scores and overall narcotic consumption, increased complication rates were seen. For these reasons, this study does not support the use of epimorph in addition to spinal anesthesia for pain control in TKA.

Kinematic alignment has increased in popularity over the last few years in an attempt to improve clinical outcomes following total knee arthroplasty (TKA).

In our unit kinematic alignment has been used with patient-specific cutting guides as part of on-going clinical trials. We performed a retrospective analysis on all the TKA which had been planned to be implanted outside of the mechanical axis (0° ± 3°) based on pre-operative MRI scans and looked at their radiographic and clinical outcomes.

We identified 21 knees which had been implanted as ‘planned outliers’. All had clinical and radiographic follow up to a mean 11.6 months post op. All had a standard long leg alignment radiograph performed at 6 weeks post op to confirm alignment.

All patients had a good improvement in their Oxford Knee Scores with mean improvement from 23 pre-op to 42 at 1 year. Of our patients none had a poor clinical outcome due to the alignment of their TKA, 1 patient had a poor outcome because of a quadriceps rupture which occurred 4 months post-op. There were no post-operative radiographic abnormalities.

In our unit kinematic alignment outside of the mechanical axis is not associated with an increased rate of short term complications.

We have identified 69 patients with Vancouver B1 periprosthetic fractures around stable femoral implants. Open reduction internal fixation is the recommended treatment; however recent studies have revealed high rates of nonunion. We have reviewed the fixation techniques utilized to treat these patients, and identified outcomes in relation to rates of union, further surgery and mortality.

Patients were identified from a prospective database of all trauma admissions at Nottingham University Hospitals from 1999 to 2010. Hospital notes were independently reviewed and data retrieved.

69 patients were identified. Mean age 77 years and 63% were female. 51 (74%) occurred around total hip replacements and 18 (26%) around hip hemiarthroplasty after a previous hip fracture.

Periprosthetic fracture occurred around an Exeter stem (n=18), Charnley (n=10), Austin Moore (n=15), other (n=6). 20 patients had undergone previous revision surgery. The mean time from index surgery to fracture was 58 months (median 24) around primary stems, and 48 months (median 22) around revision stems.

6 patients (9%) were treated non-operatively. Five of these had undisplaced fractures (all healed but one required revision due to loosening) and one was too unwell.

63 patients (91%) were treated by open reduction internal fixation. Of these, single plate fixation was performed in 40 cases (64%). In the vast majority of cases, lag screw fixation of the fracture with a long (>12 hole) pre-contoured 4.5mm locking plate was utilised with cables. Both locking and cortical screws were used to achieve stable fixation (Figure 1). A double plate technique was used in 16 cases (25%), where plates were placed perpendicularly to each other (laterally and anteriorly). Strut grafts were used in 13 cases (21%). 7 patients (11%) were treated with cables alone.

23 patients have subsequently died (33%). Two have been lost to follow up and three are awaiting union. There is a mean follow-up of 35 months.

Deep infection occurred in 4 cases (6%). Non-union occurred in four cases (6%). Two of these were infected and one was treated with cables alone. Malunion occurred in one case treated with cables. One patient had a dislocation and two superficial infections occurred.

Further surgery took place in 8 patients (12%). Three of the infected cases were revised and one underwent wound washout. The two other non-unions were revised. Three further revisions were performed: one for malunion, one for aseptic loosening (treated non-operatively) and another for a second periprosthetic fracture. Superficial wound washout was performed in one case.

Mortality was 10% at 3 months, 22% at 1 year and 47% at 3 years.

We have identified that union can be achieved in the majority of cases after periprosthetic fracture fixation. Cable fixation was associated with a high complication rate (7 cases: two requiring revision surgery: one nonunion, one malunion).

We recommend that Vancouver B1 periprosthetic fractures are treated with meticulous technique to achieve anatomical reduction and fracture compression using lag screw technique and plating. Further mechanical support can be provided through the use of a second plate, cables and/or strut grafts.

The clinical results of the cemented Exeter stem in primary hip surgery have been excellent. The Exeter ‘philosophy’ has also been extended into the treatment of displaced intracapsular hip fractures with ‘cemented bipolars’ and the Exeter Trauma Stem (Howmedica).

We have identified an increase in the number of periprosthetic fractures that we see around the Exeter stem. We have also identified a particular group of patients with comminuted fractures around ‘well fixed’ Exeter stems after primary hip surgery that present a particular difficult clinical problem.

Prior to fracture, the stems are not loose, the cement mantle remains sound and bone quality surrounding the reconstruction is good, i.e. classifying it as a Vancouver B1. However the comminuted nature of the fracture makes reduction and fixation with traditional methods difficult. Therefore in these particular circumstances it is often better to manage these as B2 or even B3 fractures, with distal bypass and uncemented reconstruction.

Over an eleven-year period since 1999, 185 patients have been admitted to Nottingham University Hospitals with a periprosthetic femoral fracture around a hip replacement. These patients were identified from a prospective database of all trauma patients admitted to the institution. Of these patients we have identified a cohort of 21 patients (11%) with a periprosthetic fracture around an Exeter polished stem. Hospital notes were independently reviewed and data retrieved. Outcome data was collected with end points of fracture union, re-revision surgery and death. Data was also collected on immediate and long term post-operative complications.

The mean age was 76 years at time of fracture, and 52% were male. The mean duration between primary index surgery and fracture was 18 months (median 11 months).

15 patients were classified as Vancouver B1, and six as B2 fractures. Of the B1 fractures, 14 underwent fixation and one was treated non-operatively. Of the B2 fractures, four were revised, one was revised and fixed using a plate, and one was fixed using a double-plating technique. Prior to fracture, none of the implants were deemed loose although one patient was under review of a stress fracture which subsequently displaced.

One patient died prior to fracture union. All the other patients subsequently went onto unite at a mean of 4 months. There were no deep infections, non- or malunions. No patient underwent further surgery. Dislocation occurred in one patient and a superficial wound infection occurred in one patient which responded to antibiotic treatment. Three other patients have subsequently died at seven, twelve and fifty-three months post fracture due to unrelated causes.

In our series of patients, in addition to the more standard fracture patterns, we have identified a very much more comminuted fracture. Indeed, we have described the appearance as if the tapered stem behaves like an axe, splitting the proximal femur as a consequence of a direct axial load. As a consequence of the injury, the cement mantle itself is severely disrupted. There is significant comminution and soft tissue stripping, calling into question the viability of the residual fragments. Treatment of this type of fracture using a combination of plates, screws and cables is unlikely to provide a sufficiently sound reconstruction. In our experience we believe these fractures around previously ‘well fixed’ Exeter stems should be treated as B2/B3 injuries.

Purpose: Severe compartment syndrome is associated with renal failure, end organ damage, and systemic inflammatory response syndrome (SIRS). Intravital videomicroscopy (IVVM) is a useful tool to study capillary perfusion and inflammation in end organs such as the liver and lungs. In this study, the systemic effect of hindlimb compartment syndrome was studied using hepatic IVVM. The purpose was to measure the effect of increased hindlimb intracompartmental pressure on hepatocyte viability, inflammation, and blood flow in a rodent model.

Method: Ten Wistar rats were randomised into control (C) and Compartment Syndrome (CS) groups. Animals were anaesthetized with 5 % isoflurane. Mean arterial pressure was monitored using a carotid artery catheter. Elevated intracompartmental pressure (EICP) was induced by saline infusion into the anterior compartment of the hind limb and maintained for 2 hours between 30–40mmHg in the CS group. Two hours following fasciotomy, the liver was analyzed using IVVM to quantify capillary perfusion as a measure of microvascular dysfunction. The numbers of adherent and rolling leukocytes in venules and sinusoids were quantified to measure the inflammatory response. Irreversible hepatocyte injury was measured using a fluorescent vital dye which labels the nuclei of severely injured cells.

Results: Hepatocellular injury was significantly higher in the CS group (325±103 PI labeled cells/10-1 mm2) compared to controls (30±12 PI labeled cells/10-1 mm2)(p=0.0087). The number of adherent venular white blood cells (WBC) was significantly higher for the CS group (5±2/hpf) than controls (0.2±0.2)(p=0.0099). Volumetric blood flow was not significantly different between CS and controls.

Conclusion: After only 2 hours of compartment syndrome in this animal model, the number of activated white blood cells increased 25-fold and liver cellular injury increased 10-fold compared to controls. Marked systemic inflammation and hepatocellular damage was detected in response to isolated limb compartment syndrome. Compartment syndrome is a low-flow ischemia/reperfusion injury with a profound inflammatory response. Further research into the severe end-organ damage associated with compartment syndrome is required.

Osteoporotic vertebral fractures predispose to significant morbidity in the elderly and are strongly associated with an overall decline in health, functional status and social drift.

In recent years various surgical morphoplastic techniques have been employed in an attempt to improve on the disappointing natural history of this manifestation of biological failure.

Current evidence supporting the use of kyphoplasty versus medical management alone in the management of these factures is limited and based on several small prospective cohort studies.

We present prospectively collected data supporting the use of kyphoplasty in a U.K. based population tested by examining Visual Analogue Pain Score (VAS), vertebral height, vertebral and kyphosis angles, Oswestry Disability Index and Hospital Anxiety and Depression Score (HADS).

50 patients in our kyphoplasty group have undergone 91 kyphoplasty procedures. With a mean follow up of 6 months, the mean post-operative VAS score was 3.8 versus a pre op score of 8.5. This reduction was maintained at 6 weeks and 6 months with mean scores of 3.3 and 2.7 respectively (p< 0.001).

Functional status ODI scoring improved from a pre-operative score of 54 to 47 post-operatively, to 40 at 6 weeks, and further, to 39 at 6 months. This result was reinforced by HADS scoring at the same time intervals recording 15.0, 11.2, 11.1 and 11.7 respectively.

Post-operative radiographs demonstrated a 24% mean increase in the vertebral angle (p< 0.01) with increases in the anterior, middle and posterior vertebral body heights of 19, 31 and 9% respectively (p< 0.001). No significant improvement of kyphosis angle was identified.

The Derby experience demonstrates that kyphoplasty can improve pain and functional status and may help correct deformity after osteoporotic vertebral compression fractures.

Our experience has encouraged further recruitment for kyphoplasty as the preferred management for those patients who fail to respond to initial non-operative management.

Osteoporotic vertebral fractures predispose to significant morbidity in the elderly and are strongly associated with an overall decline in health, functional status and social drift.

Current evidence supporting the use of kyphoplasty versus medical management alone in the management of these factures is limited and based on several small prospective cohort studies. These published case series report the use of several end points, variously including Visual analogue score (VAS), Vertebral height, kyphosis angle and Oswestry disability index (ODI).

We present prospectively collected data supporting the use of kyphoplasty in a U.K. based population tested by examining VAS, vertebral height, vertebral and kyphosis angles, ODI and hospital anxiety and depression score (HADS).

40 patients in our kyphoplasty group have undergone 70 kyphoplasty procedures. With a mean follow up of 6 months, the mean post-operative VAS score was 3.9 versus a pre op score of 8.5. This reduction was maintained at 6 weeks and 6 months with mean scores of 3.7 and 3.8 respectively.

Functional status ODI scoring improved from a pre-operative score of 53 to 48 post-operatively, to 42 at 6 weeks, and further, to 41 at 6 months. This result was reinforced by HADS scoring at the same time intervals recording 15.3, 12.0, 10.1 and 11.3 respectively.

Post-operative radiographs demonstrated a 24% mean increase in the vertebral angle with increases in the anterior, middle and posterior vertebral body heights of 26, 40 and 11 % respectively. Kyphosis angle has been improved by a mean angle of 2 degrees.

The Derby experience demonstrates that kyphoplasty can improve pain and functional status and may help correct deformity after osteoporotic vertebral compression fractures.

Our experience has encouraged further recruitment for kyphoplasty as the preferred management for those patients who fail to respond to initial non-operative management.

Introduction: The Scottish Arthroplasty Project (SAP) publishes an annual report including infection rates post-arthroplasty having obtained their results from the patients’ ICD-10 codes. The aim of this project was to validate the THR infection rate for one unit as published in the 2006 Scottish Arthroplasty Project (SAP) Report.

Method: The details of the SAP results were obtained. The BGH keeps its own record of post-operative THR infections; only those that met the dates and criteria of the SAP 2006 report were included and compared. The ICD-10 coding status was analysed in more detail.

Results: Published rate of infection in the 2006 SAP report after total hip replacement is three times lower than the unit recorded. 12 patients were eligible (1.49% infection rate), the SAP report recorded 4 cases of infection.

The SAP searches for infection only using three ICD-10 codes. Six ICD-10 codes had been used to classify these 12 patients.

Discussion: A recent cardiac surgery study comparing postoperative mortality rates from hospital statistics with the central cardiac database statistics found an over reporting by the national central database.* We have found the reverse with a threefold under calculation in the national report. However the unreported figures still do not place BGH as an outlier. The reasons for the discrepancy are multifactorial; but include poor coding practice, narrow range of code searching and difficulties in diagnosing infection. This audit shows that investigating the results of not only the outlying units but also randomly picking those who appear to have excellent results is worthwhile.