Skip to Main Content

Answer Case 2

You are correct!

The correct answer is A. Tear of a hamstring muscle.

The multiple choices were: A. Tear of a hamstring muscle, B. Fracture of the femur, C. Herniated lumbar disc,D. Lyme arthritis of the right hip, E. Bakers cyst of the right knee

Explanation: All of the multiple choice diagnoses may cause thigh pain. The patient’s cross country running through woods places her at increased risk for a variety of lower body injuries as well as Lyme disease. The ability to bear weight when standing and the absence of pain on hip flexion (during the SLR maneuver) make femoral fracture and Lyme arthritis of the hip unlikely. Bakers cyst presents as a bulge in the popliteal fossa (caused by posterior extension of a knee effusion). The following table compares sciatica from a herniated disc with a local injury of the hamstring muscle.

pain extends to below the knee

pain on straight leg raise (SLR)

pain on crossed SLR

neuro symptoms and signs

prior history of back pain

thigh tenderness

Disc herniation

usually

yes

usually

sometimes

usually

sometimes

Hamstring tear

no

yes

no

no

no

yes


* Note that the physician performed a complete straight leg raise or Lasegue sign. Raising the leg stretches both the hamstrings and the sciatic nerve. Then flexing the knee releases tension on both. Then dorsiflexing the ankle restores tension on the sciatic nerve but not the hamstring. The complete sign can be used to help distinguish a mechanical cause of pain in the thigh from a radicular cause such as a herniated lumbar disc.

Bottom line: Posterior thigh pain can result from lumbar root compression or from local disorders in the pelvis, hip, or thigh. History and physical examination can help distinguish between the two. Sciatica is usually defined as posterior thigh pain that radiates below the knee. Herniated lumbar disc is a common cause of sciatica in young adults.

Return to case 2

Go to next case