Interventions for preventing and treating stress fractures and stress reactions of bone of the lower limbs in young adults.

BACKGROUND: Stress reaction in bone, which may proceed to a fracture, is a significant problem in military recruits and in athletes, particularly long distance runners.

OBJECTIVES: To evaluate the evidence from randomised controlled trials of interventions for prevention or management of lower-limb stress fractures and stress reactions of bone in active young adults.

SEARCH STRATEGY: We searched the Cochrane Musculoskeletal Injuries Group Specialised Register (April 2004), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 1, 2004), MEDLINE (1966 to September week 1, 2004), EMBASE, CINAHL, Index to UK Theses, reference lists of relevant articles and contacted trialists.

SELECTION CRITERIA: Any randomised or quasi-randomised trials evaluating interventions for preventing or treating lower limb stress reactions of bone or stress fractures in active young adults.

DATA COLLECTION AND ANALYSIS: We independently selected trials for inclusion, assessed trial quality and extracted data. Only limited data pooling was undertaken.

MAIN RESULTS: We included 16 trials. All 13 prevention trials involved military recruits undergoing training. Participants of two of the three treatment trials were military personnel. Ten prevention trials tested the effects of various foot inserts and other footwear modifications. While pooling of data was not possible, the four trials evaluating the use of "shock-absorbing" boot inserts versus control found fewer stress injuries of the bone in their intervention groups. However, the only trial showing a significant benefit lacked important information about trial design. A key issue in several trials was the acceptability, in terms of practicality and comfort, of the boot inserts. Two cluster-randomised prevention trials found no significant effect of leg muscle stretching during warm up before exercise. Pooled data from three small but very different trials testing the use of pneumatic braces in the rehabilitation of tibial stress fractures showed a significant reduction in the time to recommencing full activity (weighted mean difference -33.39 days, 95% confidence interval -44.18 to -22.59 days). These results were highly heterogeneous (I squared = 90%), which is likely to reflect the underlying differences of the trials, including differences in the control group interventions and definitions of outcomes.

AUTHORS' CONCLUSIONS: The use of shock absorbing inserts in footwear probably reduces the incidence of stress fractures in military personnel. There is insufficient evidence to determine the best design of such inserts but comfort and tolerability should be considered. Rehabilitation after tibial stress fracture may be aided by the use of pneumatic bracing but more evidence is required to confirm this.