CASE 147
By: Dr. Nizar Al-Nakshabandi MD, FRCPC
HISTORY: 47-year-old female with hand and foot pain.
What are your findings?
What is the differential diagnosis?
What are the causes?
FINDINGS:
RIGHT ELBOW RADIOGRAPHS
The AP elbow shows a large osteophyte seen arising from the medial epicondyle measuring 9 x 7 mm and likely contributing to the cubital tunnel syndrome seen on the ultrasound. The remainder of the elbow joint is unremarkable.
The Ultrasound shows the ulnar nerve is markedly thick at the upper cubital tunnel where it reaches a surface area of 13 mm² and 4 mm thickness. Following its exit from the cubital tunnel, it drops to 2.2 mm in AP thickness.
DIAGNOSIS:
Cubital tunnel syndrome.
DIFFERENTIAL DIAGNOSIS:
Various causes can be implemented such as overuse, anconeus epitrochlearis, osteophytes compressing on the epicondyle, or accessory muscle compression. Tumor compressing on the ulnar nerve such as ganglion, or osteochondroma. Cubital thickening of the retinaculum or arcuate ligament of the flexor carpi ulnaris muscle. Finally, a fracture with loose bodies can compress on the ulnar nerve.
DIAGNOSIS:
Cubital tunnel syndrome. From osteophyte arising from the medial epicondyle/condyle.
PEARLS AND DISCUSSION:
Ulnar nerve compression presents clinically as altered sensation in the little and ring fingers. Sensory loss is the first thing to go after a while clumsiness in the hand appears as the ulnar nerve is the major supplier of the intrinsic muscles of the hands. Wasting of the small muscles of the hands and ulnar side muscles of the forearm can be seen in advanced cases.
As with all nerve disorders, patients with diabetes mellitus are at increased risk of ulnar nerve symptoms.
Major risk factors for cubital tunnel syndrome are obesity and holding a tool in a constant position, performing a repetitive task. Susceptibility of baseball throwers to cubital tunnel syndrome.
Diagnosis is usually clinical. It can be confirmed with nerve conduction studies. Imaging is to confirm cubital tunnel syndrome and shows lesion such as gangliomas, neuromas or osteophytes.
Treatment is usually avoidance of provocative activities. If surgery is contemplated, then its is usually release of the cubital tunnel by incising longitudinally over the cubital tunnel. Or removing of the tumor or osteophyte compressing on the ulnar nerve.
FURTHER READING:
1. O'Driscoll S W, Horii E, Carmichael S W. et al. The cubital tunnel and ulnar neuropathy. J Bone Joint Surg [Br] 199173613–617.617 [PubMed]
2. Siqueira M G, Martins R S. The controversial arcade of Struthers. Surg Neurol . 2005;64(Suppl 1): S1, 17–20; discussion S120–21.21 [PubMed]
3. Kanazawa S, Fujioka H, Kanatani T. et al. The relation between cubital tunnel syndrome and the elbow alignment. Kobe J Med Sci 199440155–163.163
4. Miller TT, Reinus WR. Nerve entrapment syndromes of the elbow, forearm, and wrist. AJR Am J Roentgenol. 2010;195 (3): 585-94.
5. Andreisek G, Crook DW, Burg D et-al. Peripheral neuropathies of the median, radial, and ulnar nerves: MR imaging features. Radiographics. 2006;26 (5)
6. Kroonen LT. Cubital tunnel syndrome. Orthop. Clin. North Am. 2012;43 (4): 475-86.
