DORSAL WRIST PAIN: SCAPHO-LUNATE LIGAMENT INSTABILITY
Dorsal wrist pain is a very common presentation in young active sports players. Pain associated with a sense of grip weakness and a pattern of worsening when loaded in extension could suggest a Scapho-lunate ligament injury or insufficiency. Many active sports players battle with this pain for years as this is typically poorly diagnosed, as the X-rays can be normal.
There has been a recent description of a ligament complex connecting the dorsal Scapho-lunate ligament and the wrist capsular-ligament complex called the DCSL (Dorsal Capsular Scapho-lunate ligament complex). It is now understood that small ganglions are related to the interruptions of this DCSL complex and might rather present as an early instability (almost like wrist sprain) as a result of the weakness of the dorsal Scapho-lunate ligament or DCSL complex. Patients will typically complain of pain when they load weight on their wrist in extension, for example, when doing push-ups or Yoga downward dog positions. Some patients present with painful clicks or clunking when they move the wrist.
The following patient presentation is a case in point: A 46-year healthy gent presents with six months of wrist pain affecting mainly his golf. He also complains of a deep ache after busy days of activities.
His X-rays were normal, with normal Scapho-lunate intervals and angles.
Clinically, he presents with tenderness in the 3-4 Dorsal Interval as well as a painful Kirk-Watson test. An MRI was done which showed suggestions of attenuation of the dorsal Sacpho-lunate ligament and a suggestion of dorsal and volar synovitis. Of note is that, on the saggital images, an interruption of the DCSL is clearly demonstrated here.
Arthroscopical evaluation remains the best diagnostic modality as it tests the ligaments dynamically. In this case, the midcarpal joint shows pristine cartilage and a bulging floppy Scapho-lunate dorsal and volar ligament. In the midcarpal joint, the instability can be clearly identified as the probe can fit easily between the volar and dorsal parts of the Scapho-lunate interval. This Correlates to Geissler Grade 3 and EWAS Stage II C.