A Modified Muscle Sparing Posterior Technique (SPAIRE) in Hip Hemiarthroplasty for Displaced Intracapsular Fractures.

The De Morton Mobility Index (DEMMI) assessment tool is a functional test that has been validated for acute hip fracture patient rehabilitation (De Morton 2013) and can be used in the early and late post-operative phases. In particular, it measures patient mobility with no reported ceiling effect. It is completed by a research nurse; hence cognitive impairment of the patient need not prevent its use.

Raw Score Scale: 0-19 DEMMI Score Scale: 0-100 With higher scores indicating a better outcome

The Cumulated Ambulation Score (CAS) is a simple functional tool where patients are assessed daily on their ambulatory capacity by the treating rehabilitation team during the first three post-operative days, having been validated for use with acute hip fracture rehabilitation (Foss et al. 2006) and is intended to be used in the early rehabilitation phase, being applicable to patients of all cognitive levels. It will serve as a secondary outcome of which criteria are readily available in patients' records and will ensure no potential floor effect of evaluation from the DEMMI score.

CAS Score Scale Range: 0-18, with higher scores indicating better outcomes

The Oxford Hip Score is a short patient-reported measure of function and pain following hip surgery (Dawson 1996).

OHS Range: 0-48, with higher scores representing a better outcome

A generic utility index capturing 5 dimensions of health-related quality of life (Herdman 2011) 5 dimensions indicating QoL with each dimension scored in a range from 1-5 with higher scores indicating a worse outcome. The scores for each dimension are listed together to indicate a health state, for example '12345'.

Overall health scale range:0-100 with higher indicating better health

EQ-5D-5L health states, defined by the EQ-5D-5L descriptive system, may be converted into a single index value. Please see website for details.

Numeric pain Rating Scale (NRS) Participants are asked to indicate their pain in the last 24 hours on a scale from 0-10, with higher scores indicating more pain.

For details see:

Dworkin, R. H., Turk, D. C., Farrar, J. T., Haythornthwaite, J. A., Jensen, M. P., Katz, N. P., ... \& Carr, D. B. (2005). Core outcome measures for chronic pain clinical trials: IMMPACT recommendations. Pain, 113(1), 9-19.

Analgesia medication use will be recorded from patient medical notes, with a tick to indicate which (if any) of the following medications are being taken.

Medications:

Paracetamol / codeine / ibuprofen or other non-steroidal anti-inflammatory drug (NSAID) / tramadol / morphine / oxycodone / or other

AE will be recorded, defined as any negative consequence of care that results in unintended injury or illness that may or may not have been preventable. For example:

A physical event, A psychological event (e.g., depressed mood). A laboratory event (e.g., elevated blood sugar). An increase in the severity/frequency of a pre-existing symptom or condition

An AE is considered serious if it poses a threat to the patient's life or functioning.The FDA defines a SAE as any untoward medical occurrence that:

Results in death, or Is life-threatening (places the patient at risk of death), or Requires or prolongs an existing hospitalization, or Causes persistent or significant disability or incapacity, or Is a birth defect, or Requires medical intervention to prevent one of the above outcomes

These will include records of surgical complications: categorized as dislocation, nerve injury, vascular injury, periprosthetic fracture, infection, need for re-operation (with reasons).

Length of stay in hospital for the acute hospital admission time will be recorded as number of days in hospital. Likely to be between 4 and 10 days. Length of stay will also be recorded for the total Trust stay (super-spell) that includes any time spent at rehabilitation units.

Participant's place of residence, recorded as:

• own home,
• residential/supported living,
• nursing home or
• other. These data will be collected from clinical notes to capture location pre-fracture. It will be collected from patient notes indicating the discharge destination, and will be collected at post operative day (POD) 120.

The ASA measure of physical status of the patient at the time of the operation will be recorded from surgical notes.

Scale 1-5, with higher indicating worse health status

We will conduct up to 20 semi-structured telephone interviews with patients (10 in each arm) to examine their experience of the impact of surgery and recovery period, including factors such as pain, mobility, function, independence and quality of life. Participants will be sampled from across the hospital sites taking part in the trial. The patient and public involvement group will advise on the design of the interview schedule.

Interviews will be conducted at POD120

Date of birth will be sourced via patient records and checked with patient at POD 3.

Gender will be sourced via patient records and checked with patient at POD 3.

Patient (or consultee if patient cognitively impaired) will be asked to indicate patient ethnicity at POD 3.

Patient level of cognition - (impaired or not impaired) will be obtained from the operation notes.

Before the operation the surgical team make a clinically informed decision about whether the patient is able to consent to the operation themselves (not impaired) or lacks capacity (impaired) and will need a consultee to consent to surgery on their behalf. The outcome of this assessment (which is derived using the Abbreviated Mental Test (AMT)) is detailed in the patient's medical notes. A broad categorisation of 'impaired' (if patient required a consultee to consent to surgery) or not impaired (if patient was able to consent to surgery themselves) will be derived from the patient's medical notes, and recorded for this study.