Knee Pain From Cycling - Case Study

39-year-old male, 185cm 73 kilos. Normally fit and well, significant past medical history other than Hypermobility of 4 or more joints including his knees. No traumatic injuries, ACL injury to right knee playing rugby but fully recovered now.

History of Left Knee Pain: Anterior and lateral knee pain when cycling . Slow onset and no traumatic injury. Pain lasts for a few days post ride but doesn't occur with other sports like running or day to day activities. Some loss of power to right leg at bottom of pedal stroke

Knee pain aggravating factors: riding for distances over 25km and worse when going up hill or pushing hard on the pedals. Can also happen on turbo trainer with hard low cadence efforts.

Other Pain Areas: He also reports getting pain referring up the outside of leg to left hip

Physiotherapy Observations: Left leg longer than right by 5mm this has results in a standing posture where the left iliac crest of the pelvis appears higher than the right . In supine lying It was observed the left femur is longer than the right where as the left and right tibias are equal in length. The left foot is also longer by 4mm.

Movement Analysis: When squatting there is excessive supination of the right foot while the left over pronates. these differing movements are exaggerated further when lunging or a single leg squat. Both movements cause mild left knee pain and some tightness into the left IT band.

Physiotherapy Assessment and Tests

Knees: full range of movement through flexion, extension, no pain with over pressure of patella tendon or patella glide,  left equals right.

Muscle strength and flexibility tests ; However palpation of of left patella tendon and IT band he reported pain. Both quads and hamstrings were tight but appropriate functional length for cycling and power was 5/5. However left Glut Max,/Min were 3/5 when compared with right

Knee Special Tests: ACL, MCL and PCL ligaments where intact. Meniscus of left knee was pain free on testing with no evidence of locking.

Left knee tests found evidence of patella tendonitis and IT band insertional pain.

Left Hip: Had full range of movement but some pain reported into full flexion with over pressure. Hip special tests found some pain into internal rotation.

Physiotherapy Treatment: I prescribed a strength and flexibility programme for the above symptoms which I will review in 6 weeks time to see if on testing they are helping both his muscle function which in addition fit they need addressing to aid recovery. I also advised on how to avoid the aggravating positions for both his left knee and hip when off the bike. Of course, in some situations full knee flexion can’t be avoided but instead controlled with improved awareness of how he is performing the movement and what muscle groups he is using.

The Bike Fit: Found his saddle was too high leading to toe pointing on the right and excessive pelvic lateral movement. The saddle was too far forward causing excessive loading into his quads and hands. His left knee was kicking out to the left which got worse with lower cadence tests. His cleat position was too far forward and not in between the 1st and 5th Met heads. They weren't off set either to allow for the foot length difference of 4mm.

Note left knee is tracking out prior to any changes to bike or cleat set up.

The Saddle Pressure Mapping Assessment: Found there was over loading through the right sit bone when compared with the right both on the hoods and drops. This also became more extreme with harder pedalling.

Image on left shows right sit bone loading more than left due to the left leg being longer. After fitting a 5mm shim to right cleat the pelvic loading improved as shown in right hand image.

Changes To Bike Set up: saddle down 10mm to open up his hips and allow his hamstrings to innovate as they were working out of range. The saddle was angled down to op up the hips. I also shortened and raised the handlebar stem to both open up his left hip. I also fitted a 5mm shim under the right cleat which stopped the left knee from tracking out. I also fitted inner soles to stabilise his feet from over pronating on the left and supinating on the right even after fitting the cleat shim. I off set his cleats to allow for the foot length difference.

Follow-up Appointment: He reported the left knee, IT band and hip pain had resolved with the new bike setup. Also, he felt more power through the right leg as he can drive his heal through the bottom of the pedal stroke and smashed his PB by 2 minutes on his local 10 mile time trial.

Reviewing his exercise programme, I found he had improved muscle function including strength and flexibility of his left gluts, no pain on palpation of his left knee patella tendon. The left hip was still painful with full flexion and internal rotation but not an issue when cycling.

The long-term plan: If the left hip does become painful when cycling to consider shorter cranks from 170mm to 165mm.