A 42-year-old office worker was sent to the clinic for a second opinion by an orthopaedic surgeon from another hospital. At the age of 18, she had an ACL reconstruction using the extended Macintosh technique where a strip IT band is mobilised and left attached distally, passed through a tibial tunnel round the back of the lateral femoral condyle, and anchored to it with a screw and ligament washer.

She had developed anterior knee pain and had had an MRI scan. The images were compromised by metal artefact from the screw, but the radiologist had reported that she might have pigmented villonodular synovitis (PVNS). The patient reported that she had been told that she would need a knee replacement. The referring surgeon was asking for advice on the management of her anterior knee pain.

The patient stated that the left knee was normal up until 5 years previously when she had undergone an abdominoplasty. During the operation the left common femoral artery had been damaged and required vascular repair. Following this she had symptoms of numbness down the inside of her thigh to the knee, with a feeling of cold water being drizzled down from time to time. She also had intermittent pain down the front of the knee with a burning sensation behind the kneecap. This occurred about once a month, was spontaneous in onset, and could last between 3 days and 3 weeks. During this time the knee did not swell. She was unable to fully straighten her knee. When the knee was painful, she needed to use a stick. When this occurred, the pain was worse with weight-bearing and better with rest.

She always had to sleep with her knee slightly flexed. She had been to the Emergency Department of her local hospital on one occasion with the pain. She was given painkillers and diazepam, which helped. She had seen her General Practitioner who had sent her to the local orthopaedic surgeon. She had not been seen by any other specialist or allied health professional.

She had been told that she had severe arthritis and needed a knee replacement but was too young for this. She was aware she was overweight, but this was related to her having polycystic ovary syndrome.

She was not sure what we could do but was looking for a diagnosis.