The Portland Pivot Kick Test: A Physical Examination Maneuver to Detect Mechanical Symptoms From a Medial Meniscus Tear

Abstract

Medial meniscus tears are quite common. Controversy exists over the efficacy and indications for arthroscopic partial medial meniscectomy. Some authors suggest that surgery may be indicated for patients with mechanical symptoms. There is no gold-standard method to define or detect mechanical symptoms. We report a physical examination maneuver, the Portland Pivot Kick (PPK), that can be used to help detect mechanical symptoms from a medial meniscus tear. The PPK is a standardized modification of the McMurray test. The PPK has several advantages compared to the McMurray test. The examiner does not need to touch the patient, leaving less room for variability; it can be used during a virtual visit; and it is easy to teach to health care workers or research assistants with different degrees of education.

Many studies have evaluated the efficacy of arthroscopic partial medial meniscectomy versus nonoperative treatment for patients with degenerative medial meniscus tears.1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 Low enrollment rates^9,10 and relatively high crossover rates from physical therapy to surgery have led some experts to caution against making broad conclusions based on these randomized controlled trials.^11,14,15 The general consensus is that patients who have mechanical symptoms and unsuccessful nonoperative treatment may benefit from surgery.15, 16, 17, 18 However, there is no gold-standard way to define or detect mechanical symptoms from a medial meniscus tear.^14,16,17 We report a physical examination maneuver, the Portland Pivot Kick (PPK), that can be used to help detect mechanical symptoms from a medial meniscus tear. The PPK is a standardized modification of the McMurray test. The PPK has several advantages compared to the McMurray test. The examiner does not need to touch the patient, leaving less room for variability; it can be used during a virtual visit; and it is easy to teach to health care workers or research assistants with different degrees of education.

Surgical Technique

Video 1 shows how to do the PPK test.

Physical Examination Technique

• 1.The patient sits in a chair, with hips flexed to 90°, feet flat on the floor, and hip-width apart (Fig 1).
• 2.The examiner asks the patient to externally rotate the foot of the affected limb 45° (Fig 2).
• 3.Place a heavy object on the floor against the patient’s foot centered on the first metatarsophalangeal joint. For standardization, we use a 1-gallon jug of water (Fig 3).
• 4.The examiner places their foot 2 feet away from the object, parallel to the patient’s foot (Fig 3).
• 5.The examiner asks the patient to kick the object in the direction of the examiner’s foot. For the right foot, this would be kicking the object at a 45° angle forward and to the left (Fig 4).
• 6.The examiner asks, “Did that hurt?” Yes or no (Fig 5).
• 7.If the patient says “No,” the test is negative.
• 8.If the patient says “Yes,” then the examiner says, “Point to where it hurts” (Fig 5).
• 9.If the patient points to the medial knee, the test is positive (Fig 5).
• 10.If the patient points to someplace other than the medial knee, the test is negative.

Fig 1.

The patient sits in a chair, with hips flexed to 90°, feet flat on the floor, and hip-width apart.

Fig 2.

The examiner asks the patient to externally rotate the foot of the affected limb 45°.

Fig 3.

Place a heavy object on the floor against the patient’s foot centered on the first metatarsophalangeal joint. For standardization, we use a 1-gallon jug of water. The examiner places their foot 2 feet away from the object, parallel to the patient’s foot.

Fig 4.

The examiner asks the patient to kick the object in the direction of the examiner’s foot. (For the right foot, this would be kicking the object at a 45° angle forward and to the left.)

Fig 5.

The examiner asks, “Did that hurt?” Yes or no. If the patient says “Yes,” then the examiner says, “Point to where it hurts.” If the patient points to the medial knee, the test is positive.

Discussion

While degenerative medial meniscus tears are quite common, they are not always symptomatic.19, 20, 21 These degenerative type tears typically occur at the free edge of the posterior horn and midbody of the meniscus, an area with poor vascularity and innervation.²² When the free edge of the torn meniscus gets caught, this pulls on the highly innervated capsular attachment, causing sharp medial knee pain. This catching sensation is what surgeons often describe as mechanical symptoms. The goal of surgical debridement is to remove the portion of meniscus that is getting caught, relieving the pain experienced by the patient.

Multiple studies have assessed the accuracy of physical examination maneuvers in detecting the presence of a meniscus tear.23, 24, 25 With the advent of magnetic resonance imaging, we now have a reliable answer to the question, “Does this patient have a meniscus tear?” The question we need to ask is, “Does the meniscus tear cause pain that can improve with surgery?” To answer this question, we need a reproducible, simple, standardized physical examination maneuver that can detect this painful catching sensation experienced by patients. We describe the PPK as this standardized physical examination maneuver that can be used in prospective studies evaluating treatment options for patients with mechanical symptoms from a medial meniscus tear.

Why another test? There are multiple physical examination maneuvers described for meniscus tears.23, 24, 25 The McMurray test is over 100 years old and likely one of the most commonly used.²⁶ In our academic setting, with providers at different stages of training and experience, this test is difficult to teach and is performed and interpreted in inconsistent ways. We have also moved into an era that utilizes virtual medicine, and we need to adapt our physical examinations to this moving landscape.²⁷ The PPK is a standardized variation of the McMurray test. The PPK uses the principles described by the McMurray test of placing an external rotation and valgus force across the knee as it moves from flexion to extension. It can easily be performed by providers as well as students and research assistants, facilitating its use in research studies. There is no need to touch the patient with this examination, so it can be done in a virtual visit. If properly validated, it could be used as a screening test for mechanical symptoms, especially by primary care providers before referral to orthopaedic surgeons. It also has the potential to improve the conversation between the patient and the provider about what portion of the knee pain might be related to the medial meniscus tear versus pain from osteorathritis. The PPK does have several limitations. It can only be used for medial meniscus tears, not lateral meniscus tears. In our experience, it is often negative for patients with large bucket handle tears as most of the capsular attachment is lost with these tears. It also has not been properly validated, but studies to validate the diagnostic value of the PPK are underway.

Pitfalls and Pearls

Pitfalls

The test is less effective if the force is placed on the heel. Make sure to put the resistance at or distal to the metatarsophalangeal joint to create the external rotation force.

Pearls

If a gallon of water is not available in the examination room or in virtual visits, you can ask the patient to kick any object that will give some resistance, like the leg of a chair, a stepstool, a heavy book, or a tool box.

Disclosures

All authors (M.B., Y.T., K.R.G., S.G.M.) declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

The views expressed in this article are those of the authors and do not necessarily reflect the position or policy of the U.S. Government or the Department of Veterans Affairs.

Supplementary Data

Video 1

Video demonstration of how to do the Portland Pivot Kick test. In this video, the examiner is wearing a white coat and is sitting in a chair on the left side of the image. The right knee is under examination.