Patellofemoral instability more commonly occurs in younger population (teens > twenties, and female > male) following trauma such as twisting on a loaded flexed knee. There may be tearing of the medial soft tissue with deformity of the knee. Patella often reduces spontaneously with knee extension.

Patient reported symptoms: history of trauma, rapid onset of swelling, reports of the knee to feel loose or knee cap to slip out, audible pop, knee giving way with pain, severe pain around knee cap.

Clinical signs: effusion, possible deformity, full but painful active and passive movement and positive apprehension test.

See Day et al 2009

For example:

Apprehension Test (Video link)

Patient in supine. Clinician tries to place patella laterally while flexing the knee from fully extended position. A positive test – the patient will be apprehensive and try to stop the test.

Patella glides and position

• 1st episode and each acute episode immobilise at A&E for 2 weeks
• PEACE and LOVE and early rehab VOM activation
• Recurrent - intense quad and lower limb conditioning
• 1st time responding 6-8 weeks progressive exercise ortho referral protocol

Patient centred care

Treatment should take into account individual patient needs, preferences, expectations and functional status.  Clinical reasoning should inform treatment based on subjective and objective findings.  Good communication between therapist and patient is essential if a successful outcome is to be achieved.  Treatment options should be clearly explained so that patients can make informed decisions with regard to their care and management.

First episode and each acute

Initial treatment for managing acute patellar dislocation should be aimed at relieving symptoms through PEACE and LOVE protocol. Early rehabilitation should be commenced with focus on VMO activation.

Recurrent

Intense quadriceps and lower limb conditioning.

To provide successful tailored treatment, need understanding of anatomy and biomechanics (Greiwe, et.al. 2010).

Progressing as expected (up to 3 Rxs) before discharge or onward referral.

Refer to ortho, GP, other.

Escalation

Criteria to refer on:

•  Acute
  • Onward referral to A&E for non reduced patella dislocation
• First episode
  • Referral to A&E for x-ray to rule out osteochondritis dissecans (OCD)
  • Consider orthopaedics referral if not responding to progressive exercise after 6-8 weeks
•  Recurrent
  • Orthopaedics referral only if failure to progress after 3 months of intense rehabilitation

DAY, R.J., FOX, J.E. and TAYLOR, G.P., 2009. Neuromusculoskeletal Clinical Tests: a Clinician's Guide. London: Elsevier Health Sciences, pp. 149-186.

HONG, E. and KRAFT, M.C., 2014. Evaluating anterior knee pain. The Medical clinics of North America, 98(4), pp. 697-717, xi.

ALAIA, M.J., COHN, R.M. and STRAUSS, E.J., 2014. Patellar instability. Bulletin of the Hospital for Joint Disease (2013), 72(1), pp. 6-17. Link here (link correct as at 28/8/15)

GREIWE, R.M., SAIFI, C., AHMAD, C.S. and GARDNER, T.R., 2010. Anatomy and Biomechanics of Patellar Instability. Operative Techniques in Sports Medicine, 18(2), pp. 62-67. Link here (link correct as at 28/8/15)