Medial Elbow Flexor Tendinopathy (Golfer's Elbow)

Straightforward to treat, and routinely mislabelled in both directions.

Illness script in one line: gradual medial elbow pain over the flexor-pronator origin, worse with gripping, wrist flexion and resisted pronation, radiating into the forearm flexor mass, in a golfer, climber, thrower or manual worker — eased by rest and activity modification.

Caseload frequency: much less common than its lateral cousin. Read further: epidemiology of lateral and medial epicondylitis [1], work-related incidence [2]. The usable fact: if you're diagnosing this often, question the label.

On a medial elbow, the tendon and the ligament are one problem seen from two angles

This is the organising idea. The usual medial elbow differential sets UCL against flexor tendinopathy against ulnar neuritis as three columns. That's right. What it doesn't say is that the first two are mechanically linked.

The flexor-pronator mass is a dynamic stabiliser against valgus load. Read further: contribution to elbow valgus stability [3], flexor-pronator activity and medial elbow joint gapping [4], pain, valgus instability and flexor-pronator function [5], sites of flexor-pronator injury and their relationship with UCL injury [6].

What that means when you're standing in front of a thrower:

Testing to differentiate UCL sprains from flexor-pronator strains has been described in the International Journal of Sports Physical Therapy [7] — and the fact that a 2026 paper in a physiotherapy journal is still called a "diagnostic dilemma" tells you how cleanly this separates.

Patterns > labels. This is a spectrum, and where a patient sits on it moves.

Main problem

"Pain on the inside of my elbow when I grip." Gradual onset of medial elbow pain, worsened with gripping or wrist flexion.

Gradual is the word. A sudden onset with a pop during a throw belongs on the UCL page — see section 4.

Body chart

Medial epicondyle and the pronator–flexor origin, radiating distally into the flexor mass. Pain radiates into forearm flexor mass.

One question that sorts a lot: any numbness or tingling in the little and ring fingers? Possible mild ulnar nerve irritation on examination. Mild is fine and common. Section 4 is about when it stops being mild.

Behaviour

Worse with repetitive gripping or resisted pronation. Eased by rest and activity modification.

Aggs: gripping, wringing, screwdrivers and tools, a golf swing (particularly a fat shot or hitting the ground), climbing and hangboarding, throwing, carrying with the palm up, hammering.
Eases: rest, changing grip, backing off volume.
24-hr pattern: a sore forearm the morning after gripping points at the tendon — the page's own line for the thrower.
Severity: VAS 0–10 at best / at worst / right now.

The question worth adding for a thrower: does it hurt during the throw or afterwards, and where in the throw? Pain in late cocking and acceleration points at valgus load and moves you towards the ligament (Wilk et al. 2026). Pain with grip and general use, and a sore forearm the morning after, points at the tendon.

History

Weeks to months, load-related, with a change in volume behind it. Read further: natural course and management [8].

Ask what changed: new clubs, a coaching change, a swing change, a hangboard, a new job, a house renovation, a pre-season.

Special / screening questions

Common in golfers, climbers, throwers, and manual workers. All four earn their place.

• Age and skeletal maturity. A young thrower with medial elbow pain is section 4, not this page.
• Occupational load. Force and repetition more than posture. Read further: work-related incidence (Fan et al. 2014).
• Sport and volume. Throws per week, overs bowled, sessions on the board, rounds played.
• Ulnar nerve symptoms, and whether they wake at night with them.

The discriminator that does most of the work: does valgus stress reproduce it, and how old are they.

And the honest note: these overlap. Mild secondary ulnar nerve irritability is possible but not dominant in tendinopathy, and a tendon problem and a ligament problem in the same thrower is the norm, not an exception.