Do pre-operative abdominal exercises prevent post-operative donor site complications for women undergoing DIEP flap breast reconstruction? A two-centre, prospective randomised controlled trial

The deep inferior epigastric perforator (DIEP) flap is the gold standard for breast reconstruction using abdominal tissue. Unlike the transverse rectus abdominis myocutaneous (TRAM) flap, no rectus abdominis muscle is removed with the flap, but intra-muscular scarring can still cause post-operative complications. Strong abdominal muscles have been advocated as a prerequisite for surgery, but without any evidence as to the potential benefits. This study aimed to investigate the effect of pre-operative abdominal exercises on inpatient pain levels, length of hospital stay, post-operative abdominal muscle strength and function following a DIEP flap.Ninety-three women undergoing delayed breast reconstruction with a DIEP flap between October 1999 and November 2000 were randomly allocated to either a control or exercise group. The exercise group performed pre-operative exercises using the Abdotrim abdominal exerciser. Pre-operatively, outcome measures included trunk muscle strength measured on an isokinetic dynamometer, SF-36, rectus muscle thickness measured using ultrasound, and submaximal fitness. Post-operative pain and length of hospital stay were recorded. Subjects were reassessed using the same outcome measures 1 year post-operatively. There was a statistically significant increase in static (isometric) muscle strength and thickness pre-operatively for the exercise group. One year following surgery, there was a significant decrease in dynamic (concentric and eccentric) flexion strength for both groups, although the clinical significance of this is questionable as the majority of women had returned to pre-operative fitness and the surgery had no impact on functional activities. The static flexion strength of the control group was reduced at 1 year, whereas it was maintained in the exercise group, although this was not statistically significant. One third of women in the control group complained of functional problems or abdominal pain post-operatively compared to one fifth of the exercise group. Overall, the DIEP flap had no major impact on abdominal muscle strength for either group, demonstrating its superiority over the TRAM flap. There was no statistically significant benefit to the exercise group of the pre-operative exercises 1 year following surgery. However, there was a subjective benefit, albeit statistically nonsignificant, in terms of reduced functional problems post-operatively and improved well-being prior to surgery.

Differences in electromyographic activity in the multifidus muscle and the iliocostalis lumborum between healthy subjects and patients with sub-acute and chronic low back pain

The present study was carried out to examine possible mechanisms of back muscle dysfunction by assessing a stabilising and a torque-producing back muscle, the multifidus (MF) and the iliocostalis lumborum pars thoracis (ICLT), respectively, in order to identify whether back pain patients showed altered recruitment patterns during different types of exercise. In a group of healthy subjects (n=77) and patients with sub-acute (n=24) and chronic (51) low back pain, the normalised electromyographic (EMG) activity of the MF and the ICLT (as a percentage of maximal voluntary contraction) were analysed during coordination, stabilisation and strength exercises. The results showed that, in comparison with the healthy subjects, the chronic low back pain patients displayed significantly lower (P=0.013) EMG activity of the MF during the coordination exercises, indicating that, over the long term, back pain patients have a reduced capacity to voluntarily recruit the MF in order to obtain a neutral lordosis. In contrast, during the stabilisation exercises, no significant differences between patients and controls were found for the normalised EMG activity of the two muscles. These findings indicated that, during low-load exercises, no insufficiencies in back muscle recruitment were evident in either subacute or chronic back pain patients. During the strength exercises, the normalised activity of both back muscles was significantly lower in chronic low back pain patients (P=0.017 and 0.003 for the MF and ICLT, respectively) than in healthy controls. Pain, pain avoidance and deconditioning may have contributed to these lower levels of EMG activity during intensive back muscle contraction. The possible dysfunction of the MF during coordination exercises and the altered activity of both muscles during strength exercises may be of importance in symptom generation, recurrence or maintenance of low back pain.