This injury usually occurs in patients who have femero-acetabular impingement. These patients have either an abnormal bump on their femoral neck or an overhanging pelvic cup. In both these cases, the soft cartilaginous cup rim (labrum) gets damaged (figure 1)as the hip bends up. Initially the rim is simply peeled back but eventually it becomes torn and occasionally shredded. Patients are typically younger and very active, often taking part in sports such as running, kick-boxing, mountain biking and horse riding. Occasionally it can occur due to a severe and traumatic injury e.g. hip dislocation while playing rugby.
Patients present with deep sharp groin pain, which may only occur on full hip bending. They may or may not be an associated deep click, which can be either due to the torn labrum, or more commonly, an inflamed tendon running over the front of the hip. If the condition has been present for some time, there may also be inflammation of the tissues surrounding the hip such as the outer hip (trochanteric bursitis), the groin muscles (adductor tendonitis) or infammation of tendons in front of the hip (sartorius tendonitis).
All patients undergo specialised x-rays of the hip as well as more complex scans such as CT and Magnetic Resonance Arthrography (MRA). The MR arthrogram involves injecting dye into the hip joint prior to the scan. The allows identification of the torn cartilage. CT scans are used to accurately map out the bony deformity. This is very important when planning the surgery.
If patients are unfit for surgery they can be treated with physiotherapy, painkillers, anti-inflammatory drugs and modification of activity. However, if they have a proven labral tear, then it is recommended that they undergo key-hole hip surgery (hip arthroscopy), first to address both the torn cartilage and bony abnormality, then undergo our specialist rehabilitation afterwards. A patient who has a painful hip and a proven tear is unlikely to settle without surgical intervention.
The treatment of choice is hip arthroscopy. This allows access to both the true hip joint itself and the front of the femoral head where the bony abnormality is often located. Most patients do not have a frank tear, rather the labrum is peeled back from the acetabular rim. In those patients where there is a gross tear, there is good evidence to show that patients do better long term if the tear is repaired (using stiches or glue). Occasionally the labrum is frayed and is simply debrided back until it is stable. Once that is carried out, the rest of the joint surfaces are inspected and treated as required. If the joint surface is damaged, it can be debrided back if minor or if more severe, then specialist techniques can be carried to encourage new cartilage growth (microfracture).
If there is an underlying bony abnormality on either the femoral head or the bony pelvic cup, then that is also addressed at this stage. This is technically difficult surgery but can achieve excellent results if carried out correctly and on the right patient. Based on Professor Fehilys own experience and that of the wider orthopaedic community, certain patients do not do well from hip arthroscopy e.g. patients with significant hip arthritis, patients with severe childhood hip disease (hip dysplasia) or patients with inflammatory hip disease (e.g. rheumatoid arthritis). Occasionally, the bony deformity may be so large that an adequate bony reshaping is not possible using key-hole surgical techniques. In these cases the operation is done using an open technique and the labral tear can be addressed at the same time. In some cases, the damage caused to the joint by the impingement may be so severe that the only reliable option is a joint replacement. However, all patients are different and advantages and disadvantages of the various treatment options can be discussed at the time of your consultation with Professor Fehily.