Patellar Injury and Dislocation Follow-up
- Author: Gerard A Malanga, MD; Chief Editor: Craig C Young, MD more...
Return to Play
Patients with patellar injury and dislocation may return to play after (1) all symptoms and episodes or exacerbations have resolved and (2) full ROM and preinjury strength have been achieved in the affected limb. The timeline for return to play varies from patient to patient. In a 2000 study, Atkin et al found that at 6 months, 58% of their study population still reported deficits in function.
Some variability exists in the time required to return to play, and it depends on multiple factors, including the underlying anatomy and physiology, whether conservative or surgical treatment was used, and the type of surgical treatment performed. In a review article in 2003, Hinton et al suggested that following surgical correction of a patellar injury or dislocation, return to sports can be anticipated to occur 4-6 months after the procedure.
To prevent patellofemoral knee problems, patients must not exceed the optimal patellofemoral joint-loading capacities. In addition, enhancing quadriceps strength prevents most symptoms and pathologies. Athletes involved in soccer and weight lifting should be especially careful. Studies on prophylactic bracing for patellofemoral dysfunction have thus far been inconclusive. The variability in results from bracing is likely due to the different subtleties of patellofemoral biomechanics in each individual. Each brace fits and affects different muscle groups to different degrees in different individuals.
The prognosis for patellofemoral dysfunction and dislocation has been studied and reports of outcomes vary. Overall, conservative treatment for acute patellar dislocations yields a 30-50% chance of continuing to have long-term symptoms of instability or pain.
- Cash et al reported on a 30-year noninvasive rehabilitation treatment course for patients with and without congenital anomalies of the extensor mechanism who had an acute patellar dislocation. Of the 54 patients with congenital anomalies, 28 (52%) reported good or excellent results. Of the 20 patients without congential anomalies, 15 (75%) reported good or excellent results.
- Buchner et al evaluated a total of 126 patients who had a primary traumatic patella dislocation and were treated either conservatively, with arthroscopic exploration, or with immediate surgical repair of the parapatellar ligaments. After a mean follow-up of 8.1 years, the study reported long-term functional results as excellent or good in 85% of patients. However, the investigators also noted a recurrence rate of 26% in the total study population.
- Atkin et al investigated 74 young athletes who received standardized rehabilitation after acute patellar dislocation during sporting events. After full passive ROM and quadriceps strength were at least 80% compared with the uninvolved knee, these patients returned to sports activity. Up to 6 months after the initial insult, participation in strenuous activity, especially kneeling and squatting, was significantly reduced. At 6 months, 58% continued to note a reduced ability to fully participate.
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