Abstract
Case
Mrs S, a 37-year-old mother of three attends her GP, Dr P, complaining of lower back pain of 2 weeks' duration. After a brief consultation, she is prescribed analgesia and advised that it will settle over the next few weeks.
Three days later, the patient presents to A&E with increasing pain and inability to pass urine over the preceding 24 hours. Mrs S is admitted under the spinal surgeons, who record a significant motor deficit in the lower limbs, with sensory loss around the buttocks; an urgent magnetic resonance imaging scan demonstrates herniation of the L4/5 disc, with consequent nerve root compression. Despite prompt surgical intervention, Mrs S suffers long-term neurological sequelae.
Dr P receives notice of a claim for compensation, alleging negligence at the first consultation.
Discussion
Of all musculoskeletal complaints, back pain ranks among one of the most common and most difficult to treat. Figures reported by the National Institute for Health and Clinical Excellence suggest an annual incidence of 40% for lower back pain among the adult population. In the vast majority of these patients, the pain is self-limiting, with no sinister or surgically amenable pathology. This might be why, despite widespread educational drives, patients with serious underlying pathology at risk of neurological deficit still slip through the net.
The Medical Protection Society (MPS) continues to see claims involving both GPs and hospital doctors, alleging a failure or delay in diagnosing cauda equina syndrome. Owing to the rapidity of onset, and potentially devastating results from a delayed surgery, this is perhaps unsurprising.
Cauda equina syndrome may develop as a result of many disease processes, including malignancy, trauma and infection. Disc herniation is the most common cause and frequently occurs in patients with a history of lower back pain. Thus, patients who present ‘routinely’ with apparently benign lower back pain may subsequently develop an acute neurological condition. In such circumstances, patients' recollection of events may be distorted or influenced by subsequent developments, and allegations of negligence may be made without any substandard care. In these cases, the ability to defend a case will often be largely determined by what is recorded in the clinical notes.
Cauda equina syndrome is a seriously disabling condition, which may be missed by the unwary clinician. MPS' experience of claims highlights a number of key points for reducing your clinical risk:
Patients must be asked about ‘red flag’ symptoms. These include referred pain, urinary retention (with or without overflow incontinence), faecal incontinence, sexual dysfunction and perineal, scrotal or perianal paraesthesia. The records must document the positive and negative findings Patients should be advised to return without delay, if red flag symptoms develop. This advice may be reinforced by providing a suitable information leaflet.
An assessment of perianal sensation, together with rectal examination to identify sphinctericlaxity, may assist in reaching a diagnosis. However, in cases where cauda equina syndrome is strongly suspected, these examinations may give false reassurance. Any early suspicion of cauda equina syndrome should be referred urgently for further investigation, in accordance with local referral guidelines. It is often helpful to speak directly to the receiving orthopaedic or spinal surgeon.