Lifting up and laying down a weight causes high spinal loads

Area of Science:

• Biomechanics
• Spinal Surgery
• Orthopedics

Background:

• Activities of daily living, such as lifting objects, are common for individuals with spinal conditions.
• Understanding spinal forces during these activities is crucial for patient guidance.
• Limited data exists on spinal forces and the impact of object height during lifting tasks.

Purpose of the Study:

• To quantify spinal forces during lifting and setting down weights.
• To investigate the effect of object height and posture on spinal loads.
• To provide insights for patients with spinal problems regarding safe daily activities.

Main Methods:

• Measurements of loads on telemeterized vertebral body replacements in 5 patients.
• Investigation of lifting/setting down weights (0.01, 1.5, 3.0 kg) from different heights in standing and sitting postures.
• Inclusion of tasks performed with a stretched arm while sitting.

Main Results:

• Spinal forces reached up to 5 times the baseline of standing alone during lifting/setting down activities.
• Lifting weights with a stretched arm while sitting significantly increased maximum implant forces.
• Setting down weights generally resulted in slightly higher forces than lifting.
• Variability in forces was observed due to the lack of specific task instructions.

Conclusions:

• Lifting and setting down weights generate substantial spinal forces, potentially exceeding safe limits for patients with spinal problems.
• These activities, particularly when performed with a stretched arm while sitting, should be approached with caution or avoided.
• The findings underscore the importance of considering spinal load implications in daily activities for patient rehabilitation and safety.