The patella, shoulder and knee are the most common dislocation injuries in sport. A dislocation injury is when the two bone ends in a joint separate.
Patella dislocation (knee cap)
Patella anatomy: The patella is a triangular shape bone with the base at the superior (top aspect), and the apex at the bottom. The base is attached to the quadriceps (thigh muscles) and the apex is attached to the tibial tuberosity (a bump on the shin bone) by the patella tendon (a continuum of the quadriceps).
It lies on top of the femur (thigh bone) in the patello femoral groove (a groove on the top of the femur) and is important in protecting the front of the knee.
Dislocation: In a patella dislocation, the patella is moved out of its position in the patellofemoral groove; this is normally caused by a sudden force/ high impact or twisting. The patella is normally moved to far laterally/away from the body. If there is sudden force the patella may separate into fragments. The patella may be more likely to dislocate if there is a muscle imbalance, the ligaments are weak, and/or the groove is shallow.
Loss of function e.g. inability to move the knee
Swelling occurs immediately
Feeling of the knee giving way or the patella moving out of position
Visible movement of the patella out of position
Tenderness over the patella
Contracting your thigh muscle will activate the pain
What to do
Seek medical attention if the patella has moved back into position if it has not moved back into position seek urgent attention
A medical professional will be able to put the patella back into place safely, they may use muscle relaxants to help with this
An xray will also be done to asses if there are any associated fractures-
You may have to undergo arthroscopic (key whole) surgery to washout the joint, remove debris etc.
Acute phase treatment
Follow PRICE principle (protect, rest, ice, compression, ice)
Stop activities that put more stress on the knee
Wear supportive shoe wear to prevent the knee turning excessively inwards
Static quadriceps exercises can be started when the pain allows - with your leg straight push your knee towards the bed and hold for 5 seconds repeat 15 x
Maintain the range of movement of your knee
Your physiotherapist may also use electrotherapy and taping
Rehab after the pain has resolved and the knee is healing (2-6 weeks)
You will need to see a physiotherapist to help you regain full function of your knee
Your physiotherapist may massage the area to resolve tight tissue and may also apply tape to help you regain the correct patella tracking
Regaining full movement
Bending and straightening the knee
Knee hangs of a ball- place your knee on a ball and let the knee straighten
Quadriceps exercises- these are vital muscles to help re set the patella into its position
1.Quadriceps (thigh muscles) contractions/strengthening
- Lying on your back with your knee extended try to push your knee downwards to touch the bed- you should feel your quadriceps contracting
- Hold this position for 5 seconds. Repeat 15 times
2. Straight leg raises- also helps increase the strength of the quadriceps
- Lying on your back, with you leg fully straight lift your leg about 10cm of the bed. You should feel your thigh muscles contracting
-Try to hold this position for at least 5 seconds and then slowly lower your leg back down. Repeat 15 times
3. Wall squats with ball
- Place a ball between your legs and squat down the wall, whilst squeezing the ball maintain this position- hold for 5 seconds – repeat
Flexibility exercises- your muscles may have become tight after immobilization- tight muscles can increase your knee pain and prevent the patella from tracking properly. Stretches should be done for at least 30 seconds x 3 times.
1. Hamstring (the muscle on the back of your thigh) stretch
- Standing up, place your leg to be stretched in front of the other foot, this leg should remain straight and whilst keeping your heel on the floor your toes should point upwards. Bend the other knee slightly and bend over so both hands are on that bent knee. Keep bending over from your hips until you can feel the stretch
2. Calf stretch
- Standing with your hands toughing a wall, place your foot with your heel touching the floor and your toes pointing upwards against the wall. Lean forwards until you feel the stretch. Your heel must not leave the floor.
Hip strengthening exercises to support the position of the patella
1. Straight side leg raise- increases strength of hip abductors (muscles around hip)
- Lying on your side with your injured leg on top
- Tighten your quadriceps and lift your leg about 20cm of the bed
- Try to keep your knee and hip straight and in line with the rest of your body
- Hold for 5 seconds and then slowly lower your leg back down. Repeat 15 times
2. Clams- the same technique but your knees are bent
- a rubber Theraband can be used to increase the difficulty of this exercise
2. Glute strengthening
- lying on your front and keeping your hips and leg straight lift your leg up of the bed and hold for 5 seconds, repeat 15x
5.Bridging- helps strengthen your hip, core and hamstring muscles
-Lying on your back with your knees bent
-Slowly raise your bottom of the bed, squeezing your glutes together as you do this. Then slowly return to the starting position
- progress this to lifting of one leg
-Repeat 15 times
Simple balance exercises
- Stand with your feet together, stand on one leg (with something in front to hold onto in case)
- Put cones in a circle and trying to reach out to them (start with the cones close by and progress when ready)
- Your physiotherapist will be able to progress these exercises for you to the sporting level your require
Risk of reoccurrence
The ligaments and muscles will have been stretched after this process so it is important to maintain the strength around the knee
Because of the increase instability around the knee you should follow the guidance of your physiotherapist of when they think you have gained enough stability to return to sport.
If the knee fails to heel
2. Elbow dislocation
- The humerus (arm bone) ulnar (forearm bone on little finger side) and radius (bone on thumb side) make up the elbow joint.
Complete dislocation- the arm will look deformed
Numbness/tingling, impaired hand/arm movement if nerve supply has been disrupted
Lose of pulse in the wrist if the blood supply has been disrupted
What to do:
If the arm looks deformed, you can’t feel a pulse in your wrist, you are unable to move your hand, there is numbness in your arm/hand, you are unable to bend your wrist spread your fingers or touch your thumb with your other fingers- It is important to seek immediate medical attention as there is a risk the blood/nerve supply has been interrupted which if left untreated could result in arm loss.
The doctor will check the pulse, sensation in the hand/arm and do xrays
Acute phase treatment
You may be given a brace/sling to help you immobilize your elbow
If you have small fractures you will usually only need to wear a sling for 2-3 weeks
Large fractures will need to be internally fixed
Exercises while immobilized
After immobilization period
Extension (straightening) of the elbow Is commonly a problem after immobilization
ROM exercises- bending and straightening with over pressure
Your physiotherapist will be able to help you regain movement with hands on techniques