What is Distal Biceps Tendinopathy?
Distal biceps tendinopathy refers to the term used to describe overuse injuries to the biceps tendon at the elbow. The term distal biceps tendinosis and distal biceps tendonitis are also common terms used to describe distal biceps tendon complaints. The use of the word ‘distal’ in front of biceps indicates that the biceps tendon referred to is the tendon at the elbow, the reason behind this is that there are also biceps tendons proximally at the shoulder joint that can develop tendinopathy. For the purpose of this blog it is the elbow tendon we are referring to hence the use of the term ‘distal biceps tendon’.
The Biceps Brachii Muscle
The biceps brachii muscle consists of two heads (the name effectively taken from Latin with ‘bi’ meaning two and ‘ceps’ meaning head). The short head of biceps originates at the coracoid process of the shoulder blade and the long head of biceps originates at the supragleniod tubercle at the top of the socket of the shoulder joint. The two heads meet up and join in the upper arm where the biceps muscle then travels down the front of the arm attaching via another tendon the distal biceps tendon to the radial tuberosity at the forearm just below the elbow joint. In some individuals the distal biceps tendon has two distinct parts, each as a continuation of the short and long heads of the muscle as originating from the shoulder. In others the short and long heads of biceps blend into a common tendon.
At the elbow the muscular actions that the biceps can create include bending the elbow known anatomically as elbow flexion (moving the hand towards the mouth) and turning the hand over so the palm is facing upwards, known anatomically as forearm supination. As well as this the biceps muscle can act on the shoulder joint assisting movements and stability of the joint. The actions of the biceps muscle at the shoulder will not be discussed here since for the purpose of this blog we are only concerned with biceps tendinopathy at the elbow.
Causes Of Distal Biceps Tendinopathy
With contraction of the biceps muscle, tension is placed through the biceps tendon. When tension is excessive (too much force in a single load or repeated load of lower force but still beyond that which the biceps can withstand) then damage to the biceps tendon occurs which can result in tearing, inflammation or degeneration of the tendon. When this occurs the individual may experience pain in the front of the elbow, this pain is frequently aggravated by lifting objects as well as twisting activities of the forearm.
- This sort of tendon injury is commonly associated with weight lifting at the gym, specifically the main offenders include biceps curls and chins ups.
Theories Around The Vulnerability Of The Distal Biceps Tendon And Injury
Possible predisposition of the distal biceps tendon to injury may be as a result of relatively poor vascular supply to the tendon. This poor blood supply creates the presence of an avascular zone where blood supply is limited and hence ability to absorb load, recover and repair is limited.
Another potential predisposition for distal biceps tendon injury/degeneration stems from the idea of mechanical impingement (compression) of the biceps tendon. This compression to the tendon may occur when the forearm is pronated (a movement where the palm is turned face down towards the floor). In this pronated position the available room for the tendon is reduced due to the closing space between the two forearm bones leaving less gap for the tendon and potentially compressing the loaded tendon when work is being done.
Disclaimer: Sydney Physio Clinic provides this information as an educational service and is not intended to serve as medical advice. Anyone seeking specific advice or assistance on Distal Biceps Tendinopathy: Anterior Elbow Pain should consult his or her general practitioner, sports medicine specialist, orthopedic surgeon, physiotherapist or otherwise appropriately skilled practitioner.