Case formulation: A simplified example

Over the past few days I’ve been posting about case formulation. While I’ve presented the abductive theory of method (ATOM) which is a process of inferring from phenomena to underlying causal mechanisms, it’s not the only way to develop a formulation.  I posted on some of the other ways formulations can be developed, and today I’m going to describe a simplified formulation to show how it can work in practice. Don’t forget that when I write about patients I make sure details that can identify the individual are changed – or I describe a composite of several patients.

Robert is a 39 year old previously self-employed electrician who sustained a fracture of a his nondominant hand when he fell from a ladder two years ago.  This fracture developed into a complex regional pain disorder type i which had been slowly resolving with the use of medication, functional restoration (graded daily use of the hand), and mirrorbox therapy.  Robert presented for pain management assessment when his progress plateaued, and he became increasingly distressed.

He was assessed in a three-part comprehensive pain assessment in which he was seen by a pain management medical specialist, a functional assessor and a psychosocial assessor.  He completed a set of questionnaires prior to the assessment which were used to ‘flag’ areas for closer investigation.  Information was made available from the referrer (the GP), the case manager (clinical notes from the orthopaedic surgeon and initial physiotherapy treatment provider), and an initial workplace assessment which provided details of his work demands.

The medical assessment consists of reviewing his previous medical history, a full musculoskeletal examination, general ‘systems’ examination, current and past medications used for pain management, and pain specific examination.  The purpose is to identify whether all the appropriate investigations have been completed, the appropriate medical treatments have been pursued, and the medication regime is rationalised.

The functional assessment consists of a description of a ’24 hour day’ (activity configuration, roles), approach to activity (eg boom and bust, avoidance), basic functional baseline (eg cardiovascular fitness, lifting tolerance, grip strength), and physical examination (eg muscle length/strenth, ROM, posture).

Psychosocial assessment considers attitudes and beliefs; behaviours (including coping strategies, roles); compensation issues; diagnostic and iatrogenic problems; emotional responses including depression and anxiety; responses from family and friends (and their attitudes and behaviours); and finally, work issues.

Robert’s medical examination found that he had normal body systems including cardiovascular, respiratory, endocrine and neurological except for marked allodynia to light touch over a glove distribution of his left (nondominant) hand.  On examination, his left hand was slightly swollen compared with the right, the skin a slightly darker colour, changes evident in nail and hair growth, and cooler to touch than the right.  His scaphoid fracture had united, and there was no displacement or necrosis.

He had responded only to gabapentin for pain relief, but had also found mirrorbox therapy provided him with 45 minutes pain reduction after 10 minutes passive observation of the reflection of the unaffected hand.  He had not responded to a previous pamidronate infusion, but was taking a low dose of nortriptyline for both night sedation and pain relief.

Functionally, he had reduced range of movement at the wrist, and his grip strength on the left was 2 sd below the mean for the nondominant hand for males of his age, and by comparison with his right (dominant hand) which was 1 sd above the dominant hand mean for males of his age.  He demonstrated significant pain behaviour, cradling his hand and not using it when gesturing or removing clothing, or performing the functional tasks such as lifting a box or holding onto the exercycle handlebars.  He reported avoiding using his left hand for eating, washing his hair, buttoning shirts and doing up zips, tying shoelaces, and similar activities.  He wore a tight glove to protect the hand from inadvertent light touch or air movement, water etc.

He had stopped working, and reported that although he carried out the exercises his therapists had recommended, he avoided using his hand at any other times.

The psychosocial assessment found that he believed that the doctors had missed diagnosing a serious nerve pathology in his hand, and he thought that when his pain increased it was because the nerve was misfiring and this was a sign of further damage to his nerve.  He believed that if his pain increased he would get to the point that he would no longer be able to cope, and the results of not coping would mean he would be angry with ‘everybody’ and ‘lose the plot’. Although he had found the pain was resolving, he was very fearful this was merely a temporary change.

The majority of his behaviours have been described, but he also identified that he was isolating himself, avoiding being with friends and family because ‘my family smother me with kindness’.

He had not received weekly compensation because of difficulty getting his last tax statements to Inland Revenue, so he had no income replacement.  While his treatments were being paid by ACC, he had been having difficulty obtaining funding for transport to and from his physiotherapist, and paying for his medications.  He could not afford to employ another person to cover his work, so his business was gradually running down.

In terms of diagnosis or iatrogenic issues, he had received good information from his healthcare providers, but didn’t feel confident to ask his specialist what the term ‘CRPS’ meant.  He felt that he wasn’t ‘educated enough’ to challenge his specialists recommendation that he continue to use his hand normally, and instead he ‘pretended’ to follow their recommendations during therapy, but didn’t transfer this into everyday life.

Emotionally, he felt tearful, irritable, out of control and ‘couldn’t be bothered’ about his normal activities.  Even though his business was closing, he felt his main focus was on ‘recovery’ rather than work, and he said he felt it wasn’t really ‘real’.

Family and friends had told him to take it easy, and if his hand hurt, he should wait until it ‘got better’ before he tried to do things like returning to work or use it around the home.  His partner was frustrated and scared about their financial situation, and angry that he had been ‘taking shortcuts at work again’.

And finally, his work situation was tenuous. Being self employed, he had minimised his income for tax purposes, and had delayed putting his returns in to Inland Revenue.  He couldn’t afford to employ another worker to keep the business going, and as a result, it was quickly going under.  He loved his work, and had a number of very enthusiastic contractors who asked for him.  He was a specialist electrician who mainly wired complete environmental control systems for people with disabilities.

And tomorrow – let’s put it all together!