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Orthopaedic research roundup

Stem cell therapy may help people with damaged knees

Research published in February this year in the Journal of Regenerative Medicine(1) indicates that stem cell treatment may be able to help patients with knee damage by reducing pain, improving range of movement and stopping the spread of arthritis. Thirty patients were involved in a 12 month trial conducted by the Melbourne Stem Cell Centre, with fifteen patients following standard treatment protocols and fifteen receiving injections of 'autologous adipose-derived mesenchymal stem cells' using cells from the patient's own adipose tissue specially treated in a laboratory for up to two months. The results showed that patients treated with the stem cell injections had an improvement in pain of 69% and thirteen saw the spread of arthritis stop. The control group did not see any reduction of the spread of arthritis.

Please note the above study pertains to high quality and specific adipose tissue derived stem cell research, and cannot be generalised across all patient groups and the many varieties of stem cell derivatives. This is not the same as platelet rich plasma injections or so called stem cell centres that have mushroomed across many countries including Australia. There is currently no strong evidence for routine use of stem cells in osteoarthritis of knees and no consensus or standardisation of the type of stem cells, number of cells and best way to retrieve or culture them.

Patient specific instrumentation versus robotic – assisted technique in partial knee replacement

This research, published in September in The Knee(2) looked at whether a new low cost patient specific instrument (PSI) could be as accurate as a robotic-assisted procedure for unicompartmental knee replacement (UKP). The same group had previously compared procedures using standard instruments with those using robotic assistance and concluded that robotic assistance was 'significantly more accurate than conventional instrumentation'. In this follow up study the group reviewed thirty patients needing medial UKP and reviewed the placement of the implant one day after the procedure to see how close it was to the planned placement. The study found that placement using the PSI was not significantly different to placement using the robot assisted method and resulted in a shorter procedure (62 mins shorter than the robotic assisted method and 40 mins shorter than the standard UKP procedure). The researchers concluded that 'a novel design PSI …can safely deliver comparable accuracy to a robotic system, whilst being significantly faster than conventional instruments'.

Virtual rehab

Professor Richard de Steiger, who is deputy director at the National Joint Replacement Registry (read more about the registry here), is trialling new 'virtual rehabilitation assistants' to help patients who have undergone a knee replacement procedure with their rehab. Whereas in the past the advice to these patients was to stay in bed for over a week, it is now to get up and start moving around almost immediately (see our rehabilitation guidelines here). The virtual assistants run the patient through a series of daily exercises and goals using 3D animations. The new system was the subject of a clinical study by Deakin University(3) which showed that the virtual rehabilitation assistants averaged a hospital stay of a day less than patients not using the system. The system also frees up physiotherapists, nurses and doctors while allowing the patients to work through their rehab program themselves.

We use tele-rehabilitation techniques as an integral part of our JRC (The Joint Replacement Clinic) pathway of care. Our own data supports its use along with conventional face-to-face physiotherapist out-patient consultations before and after joint replacement surgery. We use the 360 knee systems pathway integrated into our care model. See

Nine out of ten patients for knee or hip replacement overweight or obese

As reported in our previous article (Obesity and Joint Replacement Surgery), patients who are obese have a higher risk of complications than normal weight patients. Research published in May this year(4) also showed that – at one specific NSW regional hospital – only 1 patient in 10 was 'normal' weight, with the remainder either being obese or pre-obese. The study was conducted over 10 months and reviewed 247 patients undergoing elective hip or knee replacements. It concluded that current levels of obesity among patients were resulting in increased overall health costs, due to longer hospital stays and higher complication rates among obese and pre-obese patients.

“There was a greater need for increased post-operative care with obese patients with greater unplanned intensive care unit admissions and medical emergency response team calls. As BMI increased the average length of stay was longer and these patients were more likely to need transfer to a rehabilitation facility despite a longer hospital stay.” said study author Conjoint Associate Lecturer in Medicine at the University of NSW Dr Vanessa Chen.


(1) Stem Cells and Regenerative Therapies: Clarification of Terminology and Potential Applications in Ageing and Neurodegenerative Disorders Journal of Regenerative Medicine Feb 2019

(2) A novel patient-specific instrument design can deliver robotic level accuracy in unicompartmental knee arthroplasty The Knee Sep 2019

(3) Patients are experiencing less pain and are getting home quicker thanks to a program supporting recovery from knee and hip replacements, developed by Deakin University and Epworth HealthCare Jul 2019

(4) Ninety per cent of hip or knee replacement patients are pre-obese or obese, says new research May 2019