12 February 2018
With the Winter Sports season in full swing, it's appropriate to recap on some knee injuries related to skiing and snowboarding - don't just hobble on with the pain, read what our knee specialist Consultant Nev Davies advises.
Significant twisting injuries can sometimes result in damage to one or more of the major ligaments that support the knee. When we have skis or snowboards attached, the lever arm effect increases the torsional (twisting) forces through the knee, with potentially more significant injuries as a result. With improvements in ski bindings in the last several years, knee injuries are less frequent but can still happen. Also, with any twisting injury inside the knee, there is increased risk of damage to the meniscal (shock absorbing) cartilages and the joint surfaces themselves (articular cartilage).
Medial Collateral Ligament (MCL) Injuries
The MCL is the most commonly injured knee ligament. This usually occurs after a twisting motion or when the knee takes a blow from the outside, for example during sports. MCL injuries are usually diagnosed clinically (by examination) but may be confirmed by an MRI scan. When the ligament is damaged on its own, it can usually be managed non-operatively with a specialised knee brace and a good course of physiotherapy and rehabilitation. In rare cases where there is chronic insufficiency of the ligament or the ligament ruptures into the joint, surgery may be needed.
Anterior Cruciate Ligament (ACL) Injuries
The ACL is a commonly damaged ligament during sporting activities, typically in sports that involve pivoting e.g. football or netball, but also on the slopes. A rupture or tear of the ACL usually results from a twisting motion of a slightly bent knee when the foot is planted on the ground, or fixed in a ski boot. The patient often feels a pop or click inside the knee and is most likely unable to continue with the activity. Most people find the knee swells up very quickly which is associated with the torn ligament bleeding into the knee.
The management of ACL injuries has been refined over the last 15 years or so. Diagnosis is usually made clinically (by history and examination) but often an MRI scan is obtained to look for other injuries that can occur at the same time e.g. meniscal tears, or articular surface damage. Treatment plans for ACL ruptures need to be discussed with each patient on an individual basis, as they can vary from non-operative options through to surgical reconstructions. The best treatment plan depends on what else is damaged, how unstable or wobbly the knee is on a day to day basis and what the patients sporting ambitions are in the future. For more information on the injury and surgical reconstruction please download the pdf booklet on ACL reconstruction from my website (www.readinghipandkneeunit.co.uk) and/or follow this link to the national ligament registry website. (www.uknlr.co.uk)
Posterior Cruciate Ligament (PCL) Injuries
The posterior cruciate ligament lies at the back of the knee and is the largest of the knee ligaments. It can be injured in isolation or in combination with other ligaments. Injury to the PCL tends to involve higher energy than injuries to the ACL. Usually a PCL injury can be diagnosed through a good clinical assessment, but sometimes it is confirmed with X-rays or MRI scan. PCL injuries can be managed non-operatively with a specialised brace and physiotherapy, as well as with surgery. The best management option is dependent on the individual patient and the pattern of their particular injury.
Lateral Collateral Ligament (LCL) and Postero-lateral Corner (PLC) Injuries
Damage to the lateral (outside) collateral ligament or the back, outer corner of the knee are much less common. There is a group of structures collectively named the ‘postero-lateral corner’ are damaged usually in combination with other ligaments after a significant high energy injury. Sometimes it is recommended that PLC injuries are repaired surgically in the acute setting. Patients with chronic injuries where there is on-going instability of the knee may require reconstructive surgery to stabilise the knee.
The meniscal shock absorbing cartilages (‘footballers’ cartilages’) are at risk of being damaged or torn during acute knee injuries. This typically involves a twisting force, especially when seen in the younger age groups. As we get older, the meniscus becomes easier to tear and such tears are frequently associated with ‘wear and tear’ or arthritic change within the knee. Clinical assessment can often pick up a meniscal tear but it is usually confirmed with an MRI scan. Small tears may not cause too many problems and the associated symptoms can sometimes settle with non-operative treatment. If a larger tear ‘flips and flaps’ around inside the knee, it can cause the inside of the knee to become inflamed and produce more fluid creating an effusion (swelling). Such an unstable tear can also cause mechanical symptoms such as catching, locking or giving out of the knee. Such symptomatic tears can be tackled with a keyhole operation called an arthroscopy. Depending on the nature and position of the tear it is either repaired or trimmed back to a ‘stable edge’. Please refer to my knee arthroscopy pdf booklet for further information at www.readinghipandkneeunit.co.uk
The joint surfaces (articular chondral cartilage) are also at risk during a knee injury. These ‘surface’ injuries can accelerate ‘wear and tear’ arthritis in the knee, so need to be identified early to ensure the best early treatment plan is followed. If small pieces of cartilage are ‘knocked off’ during an injury, they can float around the knee as a loose body, again causing troublesome mechanical symptoms such as locking or instability. An arthroscopy is a very powerful tool to diagnose such injuries because they sometimes don’t show up clearly on MRI scans. Various management options for the different types of chondral damage are available, and again are dependent on the individual patient and injury pattern.
If you have had an injury on the slopes or playing sports or if you would just like to get your knees in the best shape possible for your ski trip, please contact Debbie Rollason, secretary to Nev Davies on 07305 097137 or via e-mail firstname.lastname@example.org to arrange an appointment.
Nev Davies FRCS (Trauma & Orthopaedics)
Consultant in Trauma & Orthopaedics