Using a comparative, longitudinal study design, we studied the effects of early weight bearing and ankle mobilisation following acute repair of ruptured Achilles tendon.

Patients in Group 1 (22 males and 4 females; mean age 44.7 years [range 31–69], 11 right- and 15 left-sided ruptures) were immobilised with their ankle in gravity equinus, and encouraged to fully weight bear. They received a single cast change at 2 weeks, when the ankle was accommodated in an anterior splint, allowing full plantarflexion but not dorsiflexion above neutral.

Patients in Group 2 (23 males and 4 females; mean age 43.8 years [range 30–67], 11 right- and 16 left-sided ruptures) were immobilised in full equinus. They received a cast change at 2 and 4 weeks, when the ankle was immobilised in a plantigrade position. They were advised to weight bear 4 weeks after the operation.

Patients in Group 1 attended less outpatient visits and completely discarded their crutches at an average of 2.5 weeks after the operation. Group 2 discarded their crutches at an average of 5.7 weeks after from the operation (p=0.013). At ultrasound scan, the average thickness of the repaired tendon was 12.1 mm (SD 2), with no difference in the thickness of the ruptured tendon regardless of the method of post-operative management. There was no significant difference in isometric strength between the two groups of patients. A greater proportion of patients in Group 1 were satisfied with the results of surgery (p=0.04).

Early weight bearing with the ankle plantigrade is not detrimental to the outcome of repair following rupture of the Achilles tendon, and shortens the time needed for rehabilitation. However, strength deficit and muscle atrophy are not prevented.

Disuse atrophy is the basis for profound physiological changes of the muscles of immobilised limbs. The aim of this study was to use ultrasound to assess the quadriceps musculature and to try and measure atrophy. We monitored the effects of enforced reduction of mobility due to trauma on the intramuscular architecture of the quadriceps using high resolution real-time ultrasonography (HRRTU) in 13 skeletally mature male patients (43.2 years, range 16 to 82 years), with an isolated unilateral diaphyseal fracture of the femur or of the tibia. All patients had undergone interlocked intramedullary nailing (IIN). Using HRRTU, the pennation angles and muscle fibre lengths of vastus lateralis, the cross sectional area (CSA) of the rectus femoris, and the quadriceps muscle layer thickness (MLT) were measured in the injured and the normal contralateral limb. Repeated measurements showed the technique of measurement of the variables used in this study to be highly reproducible. There was a significant difference in the angle of pennation of the vastus lateralis in the nailed (15.4°) and the unnailed limb (21.2°), documenting that muscle atrophy causes a change to muscle architecture that results in a significant decrease in pennation angle (p = 0.0002). The muscle fibre length was significantly different (p=0.002) and there was a significant correlation between pennation angle and muscle fibre length (r=−0.51, p=0.001). There was also a significant difference in the quadriceps MLT (p=0.001) and CSA of the rectus femoris (p=0.0004) implying that the whole of the quadriceps muscle is affected.