Length of stay following an accelerated knee arthroplasty pathway is age dependent


The emphasis on reducing the number of days patients spend in hospital is growing. Performing procedures with shorter stays using enhanced recovery pathways is one method of tackling this issue. We introduced a non-selective accelerated pathway that would allow all patients having knee replacements the opportunity to have day surgery with an option to transfer to the current inpatient pathway if required. This paper describes the outcome of the new pathway.

went home on the day of surgery
For patients under 65 years
58% were discharged on Day 0


Observational cohort study of 1220 consecutive patients undergoing elective knee arthroplasty in a UK orthopaedic hospital. On admission all patients followed the new day surgery pathway and underwent minimally invasive knee replacement surgery with general or spinal anaesthesia and local infiltration. They mobilised with a physiotherapist, weight bearing as tolerated, on the day of surgery. This was achieved by a change in physiotherapy shift patterns so patients could be seen up to 22:00. Patients were discharged home was when they had been medically reviewed, had a satisfactory x-ray, received their home medications, and were safe using crutches and on the stairs. At home patients mobilised indoors, kept their knee straight and performed static quadriceps exercises. They returned to a day surgery clinic 5 days later for a wound check by a nurse, and started knee flexion with a physiotherapist. Patients who went home on day 1 followed the same pathway and those who remained in on day 2 began knee flexion then and were discharged when well and mobilising safely, but did not attend the 5 day clinic. All patients were seen again at 6 weeks. This protocol has been published (Jenkins et al 2019).


Results: Twelve orthopaedic consultants performed 1221 primary unilateral knee replacements in the 18 months from September 2016 to June 2019. Overall 572 [47%] went home on the day of surgery; 412 [34% on Day 1 and 237 [19%] on Day 2 or later. This was age dependent: For patients under 65 years 58% were discharged on Day 0 and only 14% stayed ≥2 days; whereas for patients aged 75-84 these figures were 38% and 24% respectively and for ≥85 years 17% were discharged on Day 0 and 50% stayed ≥2 days. Patient satisfaction at 6 weeks using the Surgical Satisfaction Questionnaire showed 90% of patients discharged on day 0 were very satisfied and 92% would “do it all over again”.

Conclusion(s): The accelerated pathway allowed patients of all ages including very elderly, to be safely discharged; but the probability of discharge on Day 0 decreased with age.

Cost and savings

The project did not incur any additional costs, it used standard clinical data capture. We estimate the pathway has saved in excess of £200k per annum.


Non selective pathways should be considered for all patients irrespective of age, whilst accepting that the success of a Day 0 discharge will incrementally decrease with the age of the patients.

Top three learning points

(1) High quality electronic clinical records facilitate quality improvement projects; (2) Age is only one factor in predicting length of stay; (3) Non-selective pathways improve both outcomes and productivity.

Funding acknowledgements

Supported by Physiotherapy Research Unit.

Additional notes

References: Jenkins C, Jackson W, Bottomley N, Price A, ,Murray D, Barker KL. Introduction of an innovative day surgery pathway for unicompartmental knee replacement: No need for early knee flexion. Physiotherapy 2019, 105,1:46-52.