Combined Thenar and Hypothenar Hand Syndrome (HHS) in a Patient: Case Report and Review of Literature

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Background: The HHS is a well-described clinical entity involving the ulnar artery in patients with repetitive trauma to the ulnar artery as it courses over the hamate bone. Repetitive trauma may result in aneurysmal dilatation of the artery with either subsequent occlusion or digital embolization leading to ischemia of the fingers. Revascularization is usually required to prevent tissue loss. Much less frequently encountered is the thenar hammer syndrome with radial artery involvement. Repetitive trauma to the radial artery may also result in aneurysm formation with similar adverse sequelae. We recently treated a patient in whom there was occlusion of both the distal radial and ulnar arteries producing severe hand ischemia.
Methods: This 40-year-old male presented in 2/2007 with pain in all fingers of his right hand. The patient worked as machinist and used the palm of his hand as a hammer over a period of years. He had a 20-pack-year smoking history. His medical history was otherwise unremarkable.
On examination he had normal right upper extremity pulses. No ischemic lesions of the fingers were noted. Digital plethysmography demonstrated absent flow in the right 2^nd and 3^rd digits. The digital pressures in the right 4^th and 5^th fingers were also diminished compared to the left hand. The sedimentation rate and C-reactive protein were normal. A right upper extremity arteriogram demonstrated normal proximal vessels with occlusion of the distal radial and ulnar arteries (Figure 1).
Results: The patient was taken to the operating room where he underwent exploration of the distal radial artery at which time he was found to have a thrombosed radial artery aneurysm containing fresh thrombus (Figure 2). An interposition saphenous vein graft taken from the dorsum of the foot was used for reconstruction. A six-month postoperative duplex image demonstrated a patent graft with normal digital artery pressures in all fingers of the right hand. He has had complete symptomatic relief.
Conclusions: Review of the literature in patients with the HHS or thenar syndrome demonstrates that most patients do well following interposition grafting to restore pulsatile digital artery flow. In patients with involvement of either the radial or ulnar artery alone with an intact palmar arch, arterial ligation without reconstruction to prevent further embolization has been utilized. Thrombolytic therapy has been employed in patients in whom arteriography demonstrates thrombus within the palmar arch. Cervical sympathetectomy may be used in symptomatic patients with non-reconstructible disease. One report demonstrated that many patients with HHS have histologic findings of fibromuscular dysplasia suggesting an underlying predisposition to the syndrome. Arteriography is essential in planning the diagnosis and in planning treatment. In our literature review, concomitant radial and ulnar involvement appears to be very rare.