Compression and absolute stability are important in the management of intra-articular fractures. We compared tension band wiring with plate fixation for the treatment of fractures of the olecranon by measuring compression within the fracture. Identical transverse fractures were created in models of the ulna. Tension band wires were applied to ten fractures and ten were fixed with Acumed plates. Compression was measured using a Tekscan force transducer within the fracture gap. Dynamic testing was carried out by reproducing cyclical contraction of the triceps of 20 N and of the brachialis of 10 N. Both methods were tested on each sample. Paired t-tests compared overall compression and compression at the articular side of the fracture.

The mean compression for plating was 819 N (sd 602, 95% confidence interval (CI)) and for tension band wiring was 77 N (sd 19, 95% CI) (p = 0.039). The mean compression on the articular side of the fracture for plating was 343 N (sd 276, 95% CI) and for tension band wiring was 1 N (sd 2, 95% CI) (p = 0.038).

During simulated movements, the mean compression was reduced in both groups, with tension band wiring at −14 N (sd 7) and for plating −173 N (sd 32). No increase in compression on the articular side was detected in the tension band wiring group.

Pre-contoured plates provide significantly greater compression than tension bands in the treatment of transverse fractures of the olecranon, both over the whole fracture and specifically at the articular side of the fracture. In tension band wiring the overall compression was reduced and articular compression remained negligible during simulated contraction of the triceps, challenging the tension band principle.

Introduction: Poor proprioception and imbalance between quadriceps and hamstrings have been suggested as causes for anterior knee pain. The aim of our study was to compare the proprioception of patients with anterior knee pain to a normal population and to compare the activity of quadriceps and hamstrings using electromyography (EMG) in the 2 groups.

Methods: Patients and controls between the ages 11–25 yrs were recruited into the study. The proprioception (stability index) of the patients and controls was tested using the Biodex stability system. This computerised system tests the ability of a person to balance his/her own body on a platform that moves in various directions. Surface EMG was recorded from the quadriceps and hamstrings during this test. EMG was also recorded as the patients and controls stepped onto a 20cm step. EMG activity was normalised to levels elicited during maximal isometric contractions.

Results: 18 patients and 27 controls were recruited.

We found no significant difference between the groups in the EMG intensity of vastus lateralis relative to biceps femoris, or vastus medialis relative to vastus lateralis, during the balance test or during the step up task (Mann Whitney U test all p> 0.05). We did not find any difference in the proprioceptive abilities of the two groups

Conclusion: We found no significant difference between the groups in the intensity of muscle contraction of the hamstrings relative to the quadriceps, i.e. no evidence for an imbalance in the patients. However the temporal relation between the two needs further investigation.