Back pain is a common symptom in children and adolescents. Here we review the important causes, of which defects and stress reactions of the pars interarticularis are the most common identifiable problems. More serious pathology, including malignancy and infection, needs to be excluded when there is associated systemic illness. Clinical evaluation and management may be difficult and always requires a thorough history and physical examination. Diagnostic imaging is obtained when symptoms are persistent or severe. Imaging is used to reassure the patient, relatives and carers, and to guide management.

Cite this article: Bone Joint J 2014;96-B:717–23.

Objectives

To evaluate the neck strength of school-aged rugby players, and to define the relationship with proxy physical measures with a view to predicting neck strength.

In our study, the aims were to describe the changes in the appearance of the lumbar spine on MRI in elite fast bowlers during a follow-up period of one year, and to determine whether these could be used to predict the presence of a stress fracture of the posterior elements. We recruited 28 elite fast bowlers with a mean age of 19 years (16 to 24) who were training and playing competitively at the start of the study. They underwent baseline MRI (season 1) and further scanning (season 2) after one year to assess the appearance of the lumbar intervertebral discs and posterior bony elements. The incidence of low back pain and the amount of playing and training time lost were also recorded.

In total, 15 of the 28 participants (53.6%) showed signs of acute bone stress on either the season 1 or season 2 MR scans and there was a strong correlation between these findings and the later development of a stress fracture (p < 0.001). The prevalence of intervertebral disc degeneration was relatively low. There was no relationship between disc degeneration on the season 1 MR scans and subsequent stress fracture. Regular lumbar MR scans of asymptomatic elite fast bowlers may be of value in detecting early changes of bone stress and may allow prompt intervention aimed at preventing a stress fracture and avoiding prolonged absence from cricket.

Lumbar spondylolysis is a stress fracture of the pars interarticularis. We have evaluated the site of origin of the fracture clinically and biomechanically.

Ten adolescents with incomplete stress fractures of the pars (four bilateral) were included in our study. There were seven boys and three girls aged between 11 and 17 years. The site of the fracture was confirmed by axial and sagittal reconstructed CT. The maximum principal tensile stresses and their locations in the L5 pars during lumbar movement were calculated using a three-dimensional finite-element model of the L3-S1 segment.

In all ten patients the fracture line was seen only at the caudal-ventral aspect of the pars and did not spread completely to the craniodorsal aspect. According to the finite-element analysis, the higher stresses were found at the caudal-ventral aspect in all loading modes. In extension, the stress was twofold higher in the ventral than in the dorsal aspect.

Our radiological and biomechanical results were in agreement with our clinical observations.

Low back injuries account for the greatest loss of playing time for professional fast bowlers in cricket. Previous radiological studies have shown a high prevalence of degeneration of the lumbar discs and stress injuries of the pars interarticularis in elite junior fast bowlers. We have examined MRI appearance of the lumbar spines of 36 asymptomatic professional fast bowlers and 17 active control subjects. The fast bowlers had a relatively high prevalence of multi-level degeneration of the lumbar discs and a unique pattern of stress lesions of the pars interarticularis on the non-dominant side. The systems which have been used to classify the MR appearance of the lumbar discs and pars were found to be reliable. However, the relationship between the radiological findings, pain and dysfunction remains unclear.

We studied prospectively 22 young athletes who had undergone surgical treatment for lumbar spondylolysis. There were 15 men and seven women with a mean age of 20.2 years (15 to 34). Of these, 13 were professional footballers, four professional cricketers, three hockey players, one a tennis player and one a golfer. Preoperative assessment included plain radiography, single positron-emission CT, planar bone scanning and reverse-gantry CT. In all patients the Oswestry disability index (ODI) and in 19 the Short-Form 36 (SF-36) scores were determined preoperatively, and both were measured again after two years in all patients. Three patients had a Scott’s fusion and 19 a Buck’s fusion. The mean duration of back pain before surgery was 9.4 months (6 to 36). The mean size of the defect as determined by CT was 3.5 mm (1 to 8) and the mean preoperative and postoperative ODIs were 39.5 (. sd. 8.7) and 10.7 (. sd. 12.9), respectively. The mean scores for the physical component of the SF-36 improved from 27.1 (. sd. 5.1) to 47.8 (. sd. 7.7). The mean scores for the mental health component of the SF-36 improved from 39.0 (. sd. 3.9) to 55.4 (. sd. 6.3) with p < 0.001. After rehabilitation for a mean of seven months (4 to 10) 18 patients (82%) returned to their previous sporting activity

We studied 21 former top-class competitive javelin throwers to investigate radiological and clinical symptoms in the lumbar spine many years after the end of their athletic careers. The athletes underwent clinical and radiological examinations at an average of 20 years after retiring from athletics. The Hannover questionnaire was used to evaluate functional restrictions in daily living. Degenerative changes in the lumbar spine were more marked towards the caudal aspect of the spine. Ten athletes also had spondylolisthesis, but with little progression (< 15%) throughout the observation period. Athletes both with and without radiologically demonstrated spondylolisthesis, complained of no more back problems than the normal population (93% for athletes v 86% for controls). Slight progression followed their retirement from athletics