This article reviews the current knowledge of the intervertebral disc (IVD) and its association with low back pain (LBP). The normal IVD is a largely avascular and aneural structure with a high water content, its nutrients mainly diffusing through the end plates. IVD degeneration occurs when its cells die or become dysfunctional, notably in an acidic environment. In the process of degeneration, the IVD becomes dehydrated and vascularised, and there is an ingrowth of nerves. Although not universally the case, the altered physiology of the IVD is believed to precede or be associated with many clinical symptoms or conditions including low back and/or lower limb pain, paraesthesia, spinal stenosis and disc herniation.

New treatment options have been developed in recent years. These include biological therapies and novel surgical techniques (such as total disc replacement), although many of these are still in their experimental phase. Central to developing further methods of treatment is the need for effective ways in which to assess patients and measure their outcomes. However, significant difficulties remain and it is therefore an appropriate time to be further investigating the scientific basis of and treatment of LBP.

Disc degeneration starts as an avascular necrosis. In the lower lumbar area the discs deteriorate early because of mechanical stresses. During certain early periods of degenerative changes a mechanical disorder between the annulus and the posterior longitudinal ligament may cause tiredness and pain. When the disc is completely degenerated and has lost its physical properties backache disappears.

Between January 1990 and December 2000 we carried out 226 SB Charité III disc replacements for lumbar disc degeneration in 160 patients. They were reviewed at a mean follow-up of 79 months (31 to 161) to determine the clinical and radiological outcome. The clinical results were collected by an independent observer, who was not involved in patient selection, treatment or follow-up, using a combination of outcome measures, including the Oswestry Disability Index. Pain was recorded using a visual analogue score, and the most recent radiographs were reviewed.

Survival of the device was analysed by the Kaplan-Meier method and showed a cumulative survival of 35% at 156 months when radiological failure was taken as the endpoint. The mean improvement in the Oswestry disability index scores after disc replacement was 14% (6% to 21%) and the mean improvement in the pain score was 1.6 (0.46 to 2.73), both falling below the clinically significant threshold. Removal of the implant was required in 12 patients, four because of implant failure.

These poor results indicate that further use of this implant is not justified.

Therapeutic injection of facet joints is now widely practised, but British experience has been infrequently reported. We studied the results of injecting facet joints with a corticosteroid preparation in 50 patients suffering from the "facet syndrome". Our series included a number of extra-articular injections and these "failed injections" provide a useful control group. Results indicate that only intra-articular injections are effective; certainty of joint penetration can be ensured only by the routine use of joint arthrography.

1. Primary lumbar vertebral instability or "pseudo-spondylolisthesis" varies from about 3 millimetres to 1·7 centimetres, and is perhaps the commonest radiological sign associated with lumbo-sacral pain after the third decade of life. It was observed in 28·6 per cent of 500 consecutive cases of lumbo-sacral pain. The next commonest cause is gross disc degeneration, which is a late result of instability.

2. The secondary instability that may accompany a nuclear prolapse or osteoarthritis is excluded from this discussion.

3. This lumbar instability is an early sign of "incipient disc degeneration," occurring before narrowing of the disc space, sclerosis of the epiphysial rings, or osteophyte formation becomes evident. The instability in the lower lumbar region is caused by incomplete radial posterior tears, usually between the fourth and fifth lumbar vertebrae; and in the upper lumbar region from anterior concentric fissures or slits between some of the lamellae of the annulus fibrosus.

4. As shown radiologically, lumbar instability is commonest between L.4-5 and is rare between L.5 and sacrum because the facets between L.5-S.1 normally face forwards and backwards and thus resist anterior sliding.

5. The usual direction of antero-posterior sliding in the case of the upper four lumbar vertebrae is posterior—that is, the upper vertebra is displaced backwards on the one immediately below it during full extension in the erect position. The displacement tends to disappear on forced flexion, which may cause anterior displacement. On the other hand, the reverse displacement may exist between the fifth lumbar vertebra and the sacrum.

6. Operative treatment by bone grafting is a last resort in carefully selected individuals. After operation the patient rests in bed for three months without rigid splinting. Bone grafting is best for a localised lesion (affecting only one disc); it is generally not advisable if more than two discs are involved.

7. The results in thirty patients treated by spinal fusions showed that 70 per cent had no pain and resumed work, l3·3 per cent had improvement and resumed work, and l6·7 per cent were worse or no better.

Aims. Cauda equina syndrome (CES) can be associated with chronic severe lower back pain and long-term autonomic dysfunction. This study assesses the recently defined core outcome set for CES in a cohort of patients using validated questionnaires. Methods. Between January 2005 and December 2019, 82 patients underwent surgical decompression for acute CES secondary to massive lumbar disc prolapse at our hospital. After review of their records, patients were included if they presented with the clinical and radiological features of CES, then classified as CES incomplete (CESI) or with painless urinary retention (CESR) in accordance with guidelines published by the British Association of Spinal Surgeons. Patients provided written consent and completed a series of questionnaires. Results. In total, 61 of 82 patients returned a completed survey. Their mean age at presentation was 43 years (20 to 77; SD 12.7), and the mean duration of follow-up 58.2 months (11 to 182; SD 45.3). Autonomic dysfunction was frequent: 33% of patients reported bladder dysfunction, and 10% required a urinary catheter. There was a 38% and 53% incidence of bowel and sexual dysfunction, respectively: 47% of patients reported genital numbness. A total of 67% reported significant back pain: 44% required further investigation and 10% further intervention for the management of lower back pain. Quality of life was lower than expected when corrected for age and sex. Half the patients reported moderate or worse depression, and 40% of patients of working age could no longer work due to problems attributable to CES. Urinary and faecal incontinence, catheter use, sexual dysfunction, and genital numbness were significantly more common in patients with CESR. Conclusion. This study reports the long-term outcome of patients with CES and is the first to use validated patient-reported outcome measures to assess the CES Core Outcome Set. Persistent severe back pain and on-going autonomic dysfunction were frequently reported at a mean follow-up of five years. Cite this article: Bone Joint J 2021;103-B(9):1464–1471

Aims. To determine the value of scoliosis surgery, it is necessary to evaluate outcomes in domains that matter to patients. Since randomized trials on adolescent idiopathic scoliosis (AIS) are scarce, prospective cohort studies with comparable outcome measures are important. To enhance comparison, a core set of patient-related outcome measures is available. The aim of this study was to evaluate the outcomes of AIS fusion surgery at two-year follow-up using the core outcomes set. Methods. AIS patients were systematically enrolled in an institutional registry. In all, 144 AIS patients aged ≤ 25 years undergoing primary surgery (median age 15 years (interquartile range 14 to 17) were included. Patient-reported (condition-specific and health-related quality of life (QoL); functional status; back and leg pain intensity) and clinician-reported outcomes (complications, revision surgery) were recorded. Changes in patient-reported outcome measures (PROMs) were analyzed using Friedman’s analysis of variance. Clinical relevancy was determined using minimally important changes (Scoliosis Research Society (SRS)-22r), cut-off values for relevant effect on functioning (pain scores) and a patient-acceptable symptom state (PASS; Oswestry Disability Index). Results. At baseline, 65 out of 144 patients (45%) reported numerical rating scale (NRS) back pain scores > 5. All PROMs significantly improved at two-year follow-up. Mean improvements in SRS-22r function (+ 1.2 (SD 0.6)), pain (+ 0.6 (SD 0.8)), and self-image (+ 1.1 (SD 0.7)) domain scores, and the SRS-22r total score (+ 0.5 (SD 0.5)), were clinically relevant. At two-year follow-up, 14 out of 144 patients (10%) reported NRS back pain > 5. Surgical site infections did not occur. Only one patient (0.7%) underwent revision surgery. Conclusion. Relevant improvement in functioning, condition-specific and health-related QoL, self-image, and a relevant decrease in pain is shown at two-year follow-up after fusion surgery for AIS, with few adverse events. Contrary to the general perception that AIS is a largely asymptomatic condition, nearly half of patients report significant preoperative back pain, which reduced to 10% at two-year follow-up. Cite this article: Bone Joint J 2022;104-B(2):265–273

This edition of Cochrane Corner looks at some of the work published by the Cochrane Collaboration, covering pharmacological interventions for the prevention of bleeding in people undergoing definitive fixation or joint replacement for hip, pelvic, and long bone fractures; interventions for reducing red blood cell transfusion in adults undergoing hip fracture surgery: an overview of systematic reviews; and pharmacological treatments for low back pain in adults: an overview of Cochrane Reviews