The influence of directional preference on lateral patellar dislocation: a case report

ABSTRACT

Background

There is little consensus on the conservative management of lateral patellar dislocations (LPD). Mechanical diagnosis and therapy (MDT) is an established classification system in the spinal and extremity population. This case report describes the use of MDT in the management and classification of a patient with LPD.

Case Description

The patient was a 20-year-old female with a 3-month history of left knee pain precipitated by a lateral patellar dislocation. The patient described pain and a feeling of instability with standing and walking and limitations in work and recreational activities which involve lifting, squatting, and running. Based on the patient’s response to repeated end range knee movements, the patient was found to have a directional preference (DP) for knee extension and instruction in performance of knee extension DP exercises was provided.

Outcomes

The patient’s knee examination and subsequent intervention included her responses to repeated end range knee movements. Her knee pain was abolished, and strength, function, and motion were fully restored in five visits. A minimal clinically important difference (MCID) was achieved on the Lower Extremity Functional Scale (LEFS). At discharge, the patient was able to independently manage symptoms and perform all work and recreational activities at a pre-injury level and these improvements were maintained at a 9-month follow-up.

Discussion

There are various management strategies for lateral patellar dislocation. This case demonstrated the use of classifying, subgrouping, and treating a patient with lateral patellar dislocation using the principle of DP.

Conclusion

The patient’s outcomes suggest that MDT may be used in the nonoperative management of people with LPD who present with a DP.

KEYWORDS:

• Directional preference
• knee pain
• lateral patellar dislocations classification
• derangement
• mechanical diagnosis and therapy

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.

Notes on contributors

B Chang

B Chang completed his Bachelor of Science in Clinical Health Studies in 2018 and his Doctorate of Physical Therapy in 2020 from Ithaca College. He graduated from the McKenzie Institute USA Orthopedic Residency Program in 2021 and completed his board certification in orthopedics in 2022, this was followed by a Diploma in MDT in 2022. He is a fellow in training through The McKenzie Institute USA Orthopedic Manual Physical Therapy Fellowship Program. He is continually involved in clinical research as he is a part of the McKenzie Institute Research Task Force.

RJ Schenk

RJ Schenk is a Clinical Professor of Physical Therapy at the Tufts University School of Medicine, where he teaches in the DPT program. Dr. Schenk earned his BS and MS degrees at Ithaca College and his PhD from the University at Buffalo. An AAOMPT Fellow, he is also a Diplomat in Mechanical Diagnosis and Therapy through the McKenzie Institute, USA and is active in clinical practice. He was awarded the AAOMPT “Teach I Must” Award in 2011, the McKenzie Institute Extension Award in 2016, and the Richard W. Bowling Richard E. Erhard Orthopaedic Clinical Practice Award from the AOPT in 2022 . Dr. Schenk has published in peer-reviewed journals and has presented at national and international conferences.