Conservative Care May Be Shaky After Recurrent Patellar Dislocations

Medial patellofemoral ligament reconstruction is superior to active rehabilitation in protecting against further patella dislocations

Straume-Næsheim TM, Randsborg PH, Mikaelsen JR, Årøen A. Knee Surg Sports Traumatol Arthrosc. 2022 Mar 28. doi: 10.1007/s00167-022-06934-3. Epub ahead of print. PMID: 35347375.

Full Text Freely Available

Take-Home Message

Participants with recurrent patellar dislocations that received an isolated reconstruction of the medial patellofemoral ligament and rehabilitation were less likely to report persistent patellar instability than those receiving conservative care. However, both groups had similar improvements in all other outcomes.

Background

The decision to move forward with surgery or conservative care following an injury can be difficult. Someone with a lateral patellar dislocation and no anatomical risk factors for redislocation (e.g., patella alta, trochlear dysplasia) may be an ideal candidate for an isolated medial patellofemoral ligament reconstruction (MPFLR) or conservative treatment. However, we lack information on how to advise a patient who experienced multiple patellar dislocations.

Study Goal

Straume-Næsheim and colleagues performed a randomized clinical trial among people with recurrent lateral patellar dislocations and no anatomical risk factors for another dislocation. They compared the persistence of patellar instability at 12 months between those receiving isolated MPFLR with rehabilitation or diagnostic arthroscopy and rehabilitation.

Methods

The authors recruited 61 patients between 2010 and 2019 that had 2 or more patella dislocations, tibial tuberosity trochlear groove distance <20mm, and had a positive apprehension test upon clinical examination. They then randomized 30 participants to receive an isolated MPFLR with rehabilitation (73% female; 18 years old; ~32 months with symptoms). Another 31 patients randomly received rehabilitation after a diagnostic arthroscopy (conservative care; 71% female; 20 years old; ~29 months with symptoms). Rehabilitation focused on strengthening the vastus medialis oblique, stretching the hamstrings, and neuromuscular control of the knee. The study staff assessed participants at 3, 6, and 12 months. Participants completed the following assessments: Knee injury Osteoarthritis Outcome Score (KOOS) to measure knee-related sports function and quality of life, Kujala Score to report pain and instability on patellofemoral joint, Lysholm score to assess knee function, Noyes sport activity rating to determine level of activity, modified Cincinnati knee rating system for knee symptoms and function, and a pain scale.

Results

Overall, people who received conservative care (13 cases, 42%) were 6 times more likely to report persistent patellar instability at 12 months than those receiving an isolated MPFLR (2 cases, ~7%). Both groups experienced improvements in all patient-reported outcomes and range of motion with no differences between groups. Some surgical complications were reported: 6 cases of anterior knee pain and 1 case of complex regional pain syndrome in the thigh. Ultimately, an oversight committee stopped the study early (recruited 61 out of target 100) because of the large difference in persistent patellar instability between groups.

Viewpoints

At 12-months, over 40% of the participants receiving conservative care reported persistent patellar instability. It would be helpful to know how the authors defined persistent patellar instability, but it was concerning since the oversight committee stopped the trial. Despite the significant disparity in instability concerns, both groups had comparable improvements in other outcomes. Hence, if a patient primarily focuses on improving pain without concerns for recurrent instability, then conservative care may be appropriate and avoids the risk of surgical complications. However, if a patient plans to return to sport and has concerns about recurrent instability, an isolated MPFLR may be ideal.

Clinical Implications

Medical professionals and patients need to discuss the primary goal after a patient experiences multiple patellar dislocations. Based on that discussion, they should consider the advantages and disadvantages of each treatment approach.

Questions for Discussion

Which route did your patients with lateral patella dislocations take, conservative or surgical? What were their outcomes? Did they have another dislocation or complain of instability?

Written by: Jane McDevitt
Reviewed by: Jeffrey Driban

4 Comments

Mallory Belbey on June 1, 2022 at 1:59 am

I relate a lot to this article because I suffered from a traumatic patellar dislocation a little over a year ago. When it came to what route I would be going for, my doctor and I unanimously decided on receiving MPFL reconstruction due to the events that happened after my initial dislocation. My doctor was going to recommend I start conservation treatment once my swelling had gone down but in-between the day of my accident and the day of my MRI (a total of 5 days) I had re-dislocated my patella 3 times when that span of time. Neither my doctor nor I essentially trusted my leg to be able to do anything functional and I was deemed a perfect fit for surgery. I received the surgery about 6 weeks after my accident and it took about 9 and a half months to recover from my surgery. Within my recovery time, I was having back issues from an unrelated injury, patellar tendinitis in the surgical leg, and COVID so all 3 of those things set back my recovery time. As of right now, I am doing amazing and haven’t had any issues of my patella being unstable or had another dislocation. Am I still scared to do certain things because I am afraid it will happen again, yes but I am slowly getting over my fear and getting back to my old self.

Bryonna Woofter on June 2, 2022 at 2:16 am

The patient I had 2 years ago, who had a lateral patella dislocation took the conservative route of treatment. The patient chose this route because it was their first patella dislocation and did not have severe pain after the patella was replaced. Following the 3.5-week rehab program the patient felt 100% back to strength and returned to play. This patient did not have another dislocation occur and did not complain of instability after the rehab program was complete. The patient did complain of instability in the early stages of rehab but felt stable by the end. The patient did continue rehab 2-3 times a week to maintain stability and strength throughout the remainder of the season.

Narasha Lynch on June 10, 2022 at 12:04 am

As a Masters student I have not encountered many patients with lateral knee dislocation, so i have not seen first hand the differences between those who take the conservative route or the surgical route. But, the patient I did encounter with lateral knee dislocation took the conservative route because they didn’t feel severe pain after their patella was put back in place and it was their firs time dislocating their patella. They completed their rehab plan and was able to return to play at the level they were before the dislocation. Though they were able to efficiently progress through the rehab they did experience some instability in the beginning but towards the end they felt stable. During the time that I was there they did not experience another lateral knee dislocation.

Emma Stith on June 14, 2022 at 7:00 pm

I have worked with patients who have gone through conservative routes and surgical routes following lateral patella dislocation. One of the athletes that I worked with originally managed conservatively and was able to return to play following rehabilitation and complete the remainder of their collegiate soccer season. But, a few months later suffered secondary dislocation during an offseason training that was managed with MPFLR. This athlete reports high satisfaction with knee stability post surgery than they had with the conservative care and has not had another incidence of injury. Although this athlete ended up going the surgical route, I have had success with conservative management for an isolated lateral knee dislocation with a high school athlete.

Mallory Belbey on June 1, 2022 at 1:59 am

I relate a lot to this article because I suffered from a traumatic patellar dislocation a little over a year ago. When it came to what route I would be going for, my doctor and I unanimously decided on receiving MPFL reconstruction due to the events that happened after my initial dislocation. My doctor was going to recommend I start conservation treatment once my swelling had gone down but in-between the day of my accident and the day of my MRI (a total of 5 days) I had re-dislocated my patella 3 times when that span of time. Neither my doctor nor I essentially trusted my leg to be able to do anything functional and I was deemed a perfect fit for surgery. I received the surgery about 6 weeks after my accident and it took about 9 and a half months to recover from my surgery. Within my recovery time, I was having back issues from an unrelated injury, patellar tendinitis in the surgical leg, and COVID so all 3 of those things set back my recovery time. As of right now, I am doing amazing and haven’t had any issues of my patella being unstable or had another dislocation. Am I still scared to do certain things because I am afraid it will happen again, yes but I am slowly getting over my fear and getting back to my old self.
Bryonna Woofter on June 2, 2022 at 2:16 am

The patient I had 2 years ago, who had a lateral patella dislocation took the conservative route of treatment. The patient chose this route because it was their first patella dislocation and did not have severe pain after the patella was replaced. Following the 3.5-week rehab program the patient felt 100% back to strength and returned to play. This patient did not have another dislocation occur and did not complain of instability after the rehab program was complete. The patient did complain of instability in the early stages of rehab but felt stable by the end. The patient did continue rehab 2-3 times a week to maintain stability and strength throughout the remainder of the season.
Narasha Lynch on June 10, 2022 at 12:04 am

As a Masters student I have not encountered many patients with lateral knee dislocation, so i have not seen first hand the differences between those who take the conservative route or the surgical route. But, the patient I did encounter with lateral knee dislocation took the conservative route because they didn’t feel severe pain after their patella was put back in place and it was their firs time dislocating their patella. They completed their rehab plan and was able to return to play at the level they were before the dislocation. Though they were able to efficiently progress through the rehab they did experience some instability in the beginning but towards the end they felt stable. During the time that I was there they did not experience another lateral knee dislocation.
Emma Stith on June 14, 2022 at 7:00 pm

I have worked with patients who have gone through conservative routes and surgical routes following lateral patella dislocation. One of the athletes that I worked with originally managed conservatively and was able to return to play following rehabilitation and complete the remainder of their collegiate soccer season. But, a few months later suffered secondary dislocation during an offseason training that was managed with MPFLR. This athlete reports high satisfaction with knee stability post surgery than they had with the conservative care and has not had another incidence of injury. Although this athlete ended up going the surgical route, I have had success with conservative management for an isolated lateral knee dislocation with a high school athlete.