Stress fractures of the lumbar spine
Stress fractures in the lumbar spine, particularly the pars interarticularis, are a not uncommon injury in young athletes. On average, I see about 4-7 of these in the clinic each year.
Bony strength does not reach it's peak until the mid 20s, therefore there is a vulnerability for these injuries in the adolescent athlete, particular aged 15-20. Sports involving arching back (extension) and combined rotation with this movement are higher risk activities. These include in particular, fast bowling (cricket), and tennis players (particularly with high serving load). Other sports that we see many of these injuries in include Australian Rules Football, gymnastics and throwers (especially Javelin).
A patient with this injury will often present with back pain on one side only, which they describe as being worse with fast running or throwing. The pain may persist after activity and ache for the rest of the day. On examination, the athlete is often sore with arching back movements - we look at three or four variations of extension as part of the examination. Definite diagnosis is now made with a high quality MRI scan, and sometimes a localised CT scan of the affected area to determine the size of the injury and whether there has been any attempt at healing of the bone already.
These injuries are more common with a recent increase in load, for example a higher than normal amount of fast bowling. The amount of sport in the previous 4 weeks if particularly important in predicting injury (Orchard et al, 2009)
Management of these injuries is very important. There are two types of pars stress fractures we see - early diagnosis (a recent stress fracture) and delayed diagnosis (a stress fracture that has been present for, say, 3 months or longer).
If these injuries are diagnosed early, they need a strict three months of rest from running or arching back activities. If these injuries are diagnosed later, the rest time is less as the window of opportunity for bony healing has passed. In this situation, the athlete rests until they are painfree with day to day activities as well as specific tests involving extension and rotation.
In both situations, the rest period is used to improve core stability, as well as address any other risk factors such as posture or hamstring flexibility, or technique with the chosen sport. This rehabilitation approach is followed by a graded return to running, and later on, arching back activities such as bowling or serving (tennis). We monitor the condition of the stress fracture by using specific tests after activity. The athlete should be painfree during and after return to sport
With appropriate management, these injuries can make a full recovery and return to high level sport. Cricketers such as Peter Siddle, Shane Watson and James Pattinson are good examples.
If these injuries do not have appropriate rest, more pressure is put on the adjacent structures in the spine and this can result in long term pain and disability. This is unusual but a serious complication which can be avoided with appropriate management from the Sports Physiotherapist in conjunction with a Sports Medicine Physician.