Robotic assistance in knee arthroplasty has become increasingly popular due to improved accuracy of prosthetic implantation. However, literature on the mid-term outcomes is limited especially that of hand-held robotic-assisted devices. We present one of the longest follow-up series to date using this novel technology and discuss the learning curve for introducing robotic technology into our practice.

The purpose of this single-surgeon study is to evaluate the survival, patient-reported outcomes and learning curve for handheld boundary-controlled robotic-assisted unicompartmental knee arthroplasties (HBRUKAs) at our hospital.

This retrospective study evaluates 100 cases (94 Medial, 6 Lateral) performed by a single surgeon between October 2012 and July 2018. 52% were males, mean age was 64.5y (range 47.3y-85.2y) and mean BMI was 31.3 (range 21.8–43). Both inlay (40%) and onlay (60%) designs were implanted. Patients were followed up routinely at 1 and 5 years with Oxford Knee Scores (OKS) recorded. The learning curve was determined by tourniquet times.

At a mean follow-up of 4.3 years (range 1.6y–7.3y), survivorship was 97%. There were three revisions: One case of aseptic loosening (1.5y), one case of deep-infection (3.8y) and one case of contralateral compartment osteoarthritis progression (5y). Mean 5-year OKS was 39.8. A 14.3% reduction in mean tourniquet times between the first 25 cases (105.5minutes) and subsequent cases (90.4minutes) was seen.

This single-surgeon study showed good survivorship and patient-reported outcomes for HBRUKAs at our hospital. A learning curve of approximately 25 cases was shown, with significant decreases in tourniquet times with respect to increased surgeon experience.

Background

Patients who undergo elective hip and knee arthroplasty often have multiple risk factors increasing their likelihood of suffering from hyponatraemia post operatively. Consequently suffering from hyponatraemia post elective hip and knee arthroplasty is common. Consequently we wanted to assess the occurrence of hyponatraemia in our elective arthroplasty unit, assess our effectiveness in managing this and importantly assess how its occurrence impacted on length of patient stay.

The process of gaining informed consent can be a complex and much debated pursuit, especially within a paediatric setting. The role of the trainee surgeon and its explanation to children and their families prior to an operation has not been explored from the resident surgeons' point of view. Ten face-to-face interviews were conducted with orthopaedic surgery trainees at a tertiary level paediatric hospital in Toronto, Canada. These were transcribed and subsequently thematically coded by 3 reviewers. Three main themes were identified from the interviews. 1) Surgical trainees feel their level of participation and autonomy gradually increases dependent on their observed skills and level of training. 2) Trainees feel the consent process is adequate but acknowledge it is often purposely vague with regards to their intra-operative involvement as this is often unpredictable and it avoids patient/family anxiety. 3) Trainees believe families are aware of their participation however most likely underestimate their role during operations. Trainees in surgical specialties believe their level of autonomy is variable dependent on a number of factors and that this impacts on the ability to be more specific when gaining informed consent. This must be balanced with a family's right to an appropriate understanding of their child's operation and who is performing it. It may be that further patient education regarding trainees and their role in operations would help develop a more thorough and patient centred informed consent process.

Intraoperative cell salvage involves the collection of blood directly from the operative field. The purpose of this study was to determine if its use reduces the need for postoperative allogenic blood transfusion, assess any adverse events and its effect on duration of postoperative stay in primary hip arthroplasty.

We prospectively examined the effect of intraoperative cell salvage on the need for postoperative allogenic blood transfusion. Between February 2009 and August 2010, a total of 77 patients who underwent primary total hip arthroplasty were included in the study, under the care of the senior author (KB). All patients had a diagnosis of osteoarthritis.

Intraoperative cell salvage was used in 38 patients and not used in 39 patients. We prospectively collected data on patient demographics, ASA grade, preoperative and postoperative haematological features, number of units of packed red cells transfused and the volume of intraoperative reinfused cell salvaged blood was. Total inpatient stay and any postoperative adverse events were recorded.

No patients in the cell salvage group required postoperative allogenic blood transfusion compared to three patients (7.7%) in the conventional group. Postoperative decrease in haemoglobin was less in the cell salvage group (2.57 vs. 3.3 g/dL). The mean length of postoperative inpatient stay was shorter in the cell salvage group (5.1 vs. 6.41 days). Three patients in the cell salvage group had adverse events (1 UTI, 1 hyponatraemia, 1 colonic pseudo-obstruction). Three patients in the conventional group experienced adverse events (2 superficial wound infections, 1 DVT). An average of 361mls of cell salvaged blood was reinfused (110–900mls).

We have found that the use of intraoperative cell salvage in patients undergoing primary total hip arthroplasty reduces the need for post operative allogenic blood transfusion with no increase in adverse events when compared to conventional measures of blood preserving techniques.

Hyponatraemia is one of the most common electrolyte disorders in the elderly and has considerable associated morbidity and mortality. In this study we report the prevalence and independent risk factors for the development of post-operative hyponatraemia after surgery for hip fracture.

We conducted a retrospective cohort study of 144 consecutive patients who underwent surgery after sustaining a hip fracture. Patient medical case-notes, operative notes and online biochemistry results were used to obtain relevant data which was entered into a database.

Pre-operative (30/144, 21%) and post-operative hyponatraemia (49/144, 34%) was common. However, most cases were mild (plasma sodium >130 mmol/l) and only 1% of pre-operative and 6% of post-operative patients had moderate/severe hyponatraemia (plasma sodium <130mmol/l). One of 3 post-operative deaths involved a patient with moderate hyponatraemia as a consequence of severe congestive cardiac failure. In order to determine the independent relationship between several reported risk factors and hyponatraemia we constructed a multivariable logistic regression model. Female gender, pre-operative hyponatraemia and hypotonic fluid administration were all significantly associated with the development of post-operative hyponatraemia. Age and thiazide diuretics both had positive risk associations however were not statistically significant.

Hyponatraemia is a common problem in hip fracture patients. While the majority of cases in this series were mild, 6% of patients suffered from moderate/severe hyponatraemia post-operatively. Female gender, pre-operative hyponatraemia and hypotonic fluid administration are all important and independent risk factors for the development of hyponatraemia. Hypotonic intravenous fluids should be avoided unless clinically indicated in this patient group.

Details of orthopaedic implants in Scotland are recorded on a national database. The results are used by the Scottish Arthroplasty Project to record survival and complication rates for both knee and hip replacements.

The aim of our study was to assess the accuracy of recorded data for unicompartmental knee replacements in the West of Scotland. The national database was searched for all unicompartmental knee replacements carried out in the West of Scotland between March 2000 to October 2004. All patient data was then crosschecked with hospital theatre records and case notes for confirmation of accuracy.

A total of 88 cases were coded as unicompartment joint replacements in the study period. 63 cases were confirmed as being accurate (71.6%) and 6 as being inaccurate (6.8%). 19 patient details were not available for review either from notes or theatre records (21.6%). Of those coded inaccurately, five were total knee replacements, one cemented hip hemiarthroplasty and one shoulder replacement. One case of miscoding could be accounted for as an error in documentation while in six cases no cause could be identified. Of the 63 knees confirmed as unicompartmental, seven knees had been revised within 5 years, giving a 5 year survival rate of 87.7%.

The current system used by the Scottish Arthroplasty Project in Scotland has at least a 6.8% inaccuracy rate when recording unicompartmental knee replacements.