Comminuted patella fractures

What are comminuted patella fractures?

The patella or knee cap is the largest sesamoid bone in the body. A comminuted fracture means the knee cap is shattered into three or more pieces. It's often caused by direct impact to the knee, and is a rare injury.

Symptoms of comminuted patella fractures include pain, swelling, inability to straighten (extend) your leg or walk.

Comminuted patella fractures are diagnosed by an x-ray, and an MRI if there are suspected injuries to surrounding ligaments and tendons.

A specialist (orthopaedic surgeon) should assess the comminuted patella fracture first. Surgery may not be needed if the fracture is nondisplaced with the extensor mechanism in place (i.e. you can straighten your leg). Nondisplaced means the pieces of bone remain in contact with each other or are separated by just a millimeter or two.

If surgery is not required, the patient would usually be advised to wear a range of motion brace which locks the knee in extension for 4 to 6 weeks. The patient may also need to use crutches. As the knee gradually heals, the specialist may advise the patient to increase knee flexion.

Let's have a look at how comminuted patella fractures that don't require surgery are managed using Breathe Physio and Pilates' Roadmap for Recovery. The aim is to increase the knee range of motion and increase muscles' strength, to enable the patient to walk and carry out their normal activities.

Breathe Physio and Pilates Roadmap for Recovery

Stage 1 - Pain reduction

Pain and swelling are managed by cryotherapy (icing), elevating the leg, taking pain medication as prescribed, and resting.

Fitting a ROM brace on a patient with a comminuted patella fracture

Stage 2 - Activation

As you are in a range of motion brace, your knee may become stiff and your thigh muscles will weaken. The activation stage focuses on activating, or waking up the muscles surrounding the knee cap to better support the bone.

We will take you through exercises that focus on active flexion and extension in inner ranges. We will also prescribe exercises that strengthen the quadriceps, hamstrings, glutes and core. Examples include banded knee extension, banded hamstring curls, and side-lye leg raises.

Stage 3 - Movement

Once healing gradually takes place, you may be advised by your specialist doctor to progress to full knee flexion and extension. Physiotherapy will now focus on movement techniques with good ankle, knee and hip alignment, and further muscle strengthening.

We will progress to exercises such as the stationary bike, closed kinetic chain exercises like squats and step-ups. We can also now use resistance to strengthen the gluteal muscles (such as banded clams). In time, we include lunges and proprioception exercises in your program.

Stage 4 - Strength building or return to sport

If you are an athlete, it is worthwhile to find a sports physiotherapist who you trust and work well together.

During this stage, we may use technology such as the VALD Forcedecks to measure your readiness to return to sport, by assessing your strength and motor control patterns on the injured limb. We add plyometrics, velocity, agility, power, change of direction aspects to your rehab so you can confidently return to sport.

Author: Winnie Lu

Winnie Lu

Winnie is the principal physiotherapist and Director of Breathe Physio and Pilates. Winnie has extensive experience treating athletes who compete in cycling, running and soccer/football. Winnie also has many years of experience treating lower limb amputees, and eventually getting them back to playing sports. Winnie is an associate lecturer at the University of Queensland and mentors physiotherapy students during their clinical placements at Breathe. Winnie has a passion for optimising movement and helping clients become better athletes.

References:

1. Patella Fractures: https://my.clevelandclinic.org/health/diseases/22081-patella-fracture, Cleveland Clinic. Accessed on 18 March 2024.

2. Jain, D R, Deshmukh, M (2023) Effectiveness of Physical Therapy in a Comminuted Patella Fracture Managed with Tension Band Wiring: A Case Report.